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What is the best thickener for GF onion soup?

I am using Julia's recipe with a gratinee of Gruyere cheese. It needs to be gluten free.

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    1. Dehydrated potato flakes. They dissolve and add zero other flavor. Look for instant mashed potatoes with ONLY ingredient of potatoes, do not boil. Might be $2.

      1. I don't know if I'm too late with my answer but I'd use pureed caramelized onions to thicken the soup; you're already using them, just make extra

        20 Replies
        1. re: Cherylptw

          I want to keep with the same ratio of flavors as in the recipe.

          1. re: wekick

            Well, you got two gluten issues at hand. Thickener and the baguette/bread toasted slice.

            If going natural, I say white rice flour or the dehydrated potato flakes to facsimilate the roux factor the flour adds.

            Some up front at end of onion carmelization as usual and then observe after half cook time with broth.

            Neither of the above will affect flavor from orig recipe in my eyes, but you may need to push and pull to get thickening.

            As for your toasted bread choice, I'll await news of what you chose at serving time. :-)

            1. re: jjjrfoodie

              My DIL has GF baguettes that are not bad. We are making this for a birthday party.

              1. re: jjjrfoodie

                I have eaten many French onion soups both made by me and at restaurants. Who is serving thickened French onion soup? It is usually a rich beef booze herb enhanced broth with long sumptuous strands of caramelized onions covered in a crispy toast and cheeses melted under the broiler. I am seriously confused.

                1. re: MamasCooking

                  Evidently Julia Child did. No need to be confused. There are all kinds of onion soup and yes Julia Child put a little flour in hers. We are not talking thick like pea soup but body. I would be alarmed if mine came with melted cheeses. It has to be brown and bubbly on top and something like gruyere. I ask and if it's just melted cheese, no thank you, if I am in a restaurant.

                  1. re: wekick

                    Cheese melted under a broiler = browned/bubbly. Traditional.

                    1. re: wekick

                      I suspect Julia adapted her recipe with a memory of the Lyonnaise-style of onion soup, which is somewhat thicker (though with a liaison of egg yolks).

                      1. re: wekick

                        Yes. Recipes that call for flour (and many do) use about a tablespoon sprinkled in with the onions.

                        It is not overtly thickened like gravy or a cream soup.

                        But like I said before, the flour is not necessary.

                        1. re: C. Hamster

                          Julia uses 3 tablespoons of butter browned flour.


                          I don't use flour in mine, either. I don't find any reason to dilute the flavor of the onions with a thickener. It's plenty rich the way it is.

                          By the way, I love how she recommends topping the gratinee with a combination of shredded swiss and parmesan cheeses, which is obviously a reflection of the bland state of cheese in America at the time these shows were filmed. I'd feel very comfortable adapting the recipe using a proper gruyere instead of the bland swiss/green can parmesan that she likely used in her show.


                          Mr Taster

                        2. re: wekick

                          > Evidently Julia Child did. No need to be confused.

                          See my link explaining why you're both right, MamasCooking and wekick.


                          Mr Taster

                        3. re: MamasCooking

                          Me, too. I'd never heard of thickening it, nor would I want to. I make a very beefy broth with roasted bones for it, well reduced, and lots of onions then cheese.

                      2. re: wekick

                        You're going to have the same flavors with pureeing the soup but as many have noted, onion soup is not supposed to be thick. Good luck

                      3. re: Cherylptw

                        that's what I'd do as well: my onion soup contains onions - so many that at first they barely fit into the pot - sauteed long and slow until they're a rich, thick, brown caramelized mass - and stock. The slice of bread is just there to hold up the cheese, and doesn't go on until immediately before serving time, so the soup itself is gluten-free.

                        1. re: tardigrade

                          I don't understand the OP's way of thinking that if part of the soup was pureed with the same onions used anyway, that it would not have the original flavors...any idea? Anyone?

                          1. re: Cherylptw

                            I notice he is avoiding responding to our queries too. Not sure what he is looking for.

                            1. re: Cherylptw

                              The first suggestion was to purée more onions so that would throw the ratios off from the specific recipe I am using. You could purée the soup as a whole but I have done that with some other sauces based on caramelized onions and wasn't that crazy about the taste. I have puréed other soups in the same way that usually had not as many onions and things that were starchy or at least not as flavorful as the onions. They tend to stay balanced. I have had carrots get too strong when puréed in a soup as well.

                              1. re: wekick

                                While I don't like the idea of putting flour in onion soup, I can see not wanting to thicken with pureed onions either.

                                If you use a homemade beef stock made with plenty of bones, cartilage and connective tissue, of the sort that, once cooled, is the consistency of set gelatin, the soup will have plenty of body.

                                If you still want a thickener, I would suggest arrowroot, because it will be neutral-tasting and - this is important, I think - stays clear, so your soup won't be opaque. You would add this at the end of cooking, in a slurry, just like you would cornstarch. Cornstarch added in a slurry at the end would be another option, but arrowroot would be a better choice, I think, for this application.

                                1. re: wekick

                                  We're not talking about carrots but onions which is the only vegetable in a onion soup. The onions are already caramelized so how much stronger can you possibly make them by pureeing. Makes no sense but good luck on that one.

                                  1. re: Cherylptw

                                    Consider that caramelization and pureeing are two entirely different processes. Heating the onion changes the flavor by destroying certain flavor components and removing water and allowing the caramelization of the sugars and the Maillard reaction to take place. Pureeing breaks the onions down into very tiny particles. This allows the flavors to be more efficiently dispersed in the soup making the onion taste stronger. I mentioned carrots as another example of a food that I have noticed can get strong in this way.

                          2. Why would you want to thicken onion soup? Increase the amount of onions if you want more of an onion stew. A traditional onion soup is a broth with onions, no thickeners at all.

                            12 Replies
                            1. re: smtucker

                              This is what I think also. I have never thickened onion soup.

                              1. re: smtucker

                                I am looking to replicate a specific recipe.

                                  1. re: magiesmom

                                    I referred to it in the original post but maybe I should have said "Julia Child's". Here is a link.

                                    1. re: wekick

                                      it really doesn't need flour, or any kind of thickener. it. just. doesn't.

                                      1. re: hotoynoodle

                                        I made Julia's Boca Negra without flour and it came out ok but with a slightly different texture. I might just make a batch of soup and try some of these ideas and some without any thickener and see. As daislander said, it might be about mouthfeel or it might not make a difference at all. I used to work in a food lab and mouthfeel is a big deal for some people.

                                        1. re: wekick

                                          Onion soup doesn't need flour IMO.

                                          1. re: wekick

                                            mouthfeel is a big deal for me. :)

                                            starting with a rich, gelatinous stock will give you a much rounder, but cleaner, mouthfeel than a few spoons of flour.

                                            now that i see the link, it's from julia's old show -- from the 60s? not too many people use flour in a soup like this anymore.

                                            1. re: hotoynoodle

                                              She never changed the recipe much and it is on her later shows as well. It has stood the test of time and it is lauded on many forums and blogs. I can't say what many people do in their kitchens anymore but you find recipes with and without flour. I always have a hard time sticking with a recipe but am trying to do so here. The first reason is because I have heard so many praise her recipe. The second is because we had a department store, now closed that was famous for its onion soup and the recipe is almost the same as Julia's. Everybody at our little gathering has fond memories of that soup.

                                  2. re: smtucker

                                    I'm not looking for what is traditional but what I like. A little body.

                                    1. re: wekick

                                      A rich beef stock has tons of body.

                                      It seems to me that when a recipe exists without gluten and is wonderful it is silly to use one that has gluten.
                                      The best GF foods are without gluten inherently.

                                    2. re: smtucker

                                      I'd usually add a very very small amount of Plain flour to add a bit of body. but will also add a tiny bit of Xanthan at the end to make it more feel more richer.

                                      1. re: sal_acid

                                        I bought a bag from Red Mills a while back and have found it to be an excellent thickener as well as stabilizer. It takes so little to do the job for most things and imparts no flavor of it's own. It's heat stable and will not loose it's thickening ability the long it's cooked.

                                        1. re: scubadoo97

                                          It's also a laxative, which many people surely need, but some of us do not need.

                                          1. re: MelMM

                                            At that low a dose I doubt it would be noticed by even the most sensitive

                                            1. re: scubadoo97

                                              You would be surprised. It doesn't take much xanthan gum to thicken something, and likewise, it takes very, very little to have a laxative effect. The amounts in a bottled salad dressing, for example, are well beyond the threshold.

                                            2. re: MelMM

                                              Lots of ingredients act as a laxative in certain people, like the pound of cheese used to put on top of the soup in this recipe.

                                              1. re: Cherylptw

                                                Xanthan gum is used in medicine as a laxative.

                                                1. re: MelMM

                                                  Not very commonly used in medicine. Which laxative are you talking about? Not an ingredient in most OTC preps. that I've run across.

                                                  It's most common use is a thickener and emulsifier. And used a lot in GF baking.

                                                  1. re: scubadoo97

                                                    I don't know about specific OTC laxatives (if any) that it might be in, because I do not ever take a laxative.



                                                    On that last link, click through to see tabs for "uses" and "side effects".

                                                    For me personally, xanthan gum at the levels found in bottled salad dressing and in gluten-free baked goods is sufficient for me to experience the "side effects". I have been gluten-free for 13 years, and I've had plenty of time to do controlled experiments on myself. There might be a lot of people (perhaps a majority in the US) who can benefit from this laxative effect, but for others, it is nothing but trouble.

                                        2. a vegan gelatine.. or regular. should give a could mouth feel as I have heard people say lol or tapioca starch but not to much it can get gluey

                                          4 Replies
                                          1. re: daislander

                                            I recommend gelatin as well. It's clear, flavorless and will do the job nicely without making it gloppy thick and white like corn starch or flour, but you may want to try Arrowroot... instant thickening without having to bring to a boil...

                                            1. re: Gastronomos

                                              Where do you buy arrowroot (maybe post a link to a package image?) I unsuccessfully hunted the baking aisles at a few grocery stores a couple of years ago, then just gave up.

                                              1. re: MidwesternerTT

                                                my local market has it in the spice section, but Penzey's Spices has it via mail order:


                                                1. re: MidwesternerTT

                                                  I would look in a health food store. Im Canadian so can't recommend which ones to try for you. Bobs Redmill makes it if you can find a store that carrys those products.

                                                  Im still going with gelatine as that is what thickness onion soup to begin with.

                                            2. Traditional onion soup is not thick or very creamy. But if you want to thicken your soup and not compromise the flavor integrity of it then I would suggest preparing extra caramelized onions and puree them with a blender to add in.

                                              5 Replies
                                              1. re: MamasCooking

                                                I am not looking for thick or creamy but not thin or watery. I'm just looking for a little body.

                                                1. re: wekick

                                                  OK thanks:) Anyway you do it yummy yummy yummy!

                                                  1. re: wekick

                                                    The small amount of flour called for really doesn't give the soup much body. I have made it with and without and cant tell the difference.

                                                    1. re: wekick

                                                      If you want a rigorously tested recipe with precisely formulated ratios resulting in an extremely high quality French onion soup, look to the folks at Cooks Illustrated. No gluten in their recipe.


                                                      Mr Taster

                                                  2. I think you could try potato flour. I'd use slightly less than what is called for in the recipe.

                                                    1. I make FOS all the time as it's my very favorite food.

                                                      I never use a recipe anymore but most of the recipes I have seen add a small amount of flour to the onions.

                                                      I have often forgotten to add it and the soup turns out just fine.

                                                      Skip the thickener

                                                      3 Replies
                                                      1. re: C. Hamster

                                                        I must have been making mine incorrectly then:) No flour. It always came out savory and delicious.

                                                        1. re: MamasCooking

                                                          Mine is always craveable. With or without the flour.

                                                          1. re: C. Hamster

                                                            I know. It is such a delicious dish. I will try it with flour next time just to give it a go.

                                                      2. Omit the flour thickener entirely. Onion soup traditionally doesn't include it, and it's not necessary to the dish.

                                                        For a richer mouth-feel, use a beef stock made with lots of bones & gelatinous parts - that's all the thickener an onion soup requires. If you're using stock or broth that doesn't have enough body, roast & toss some soup bones in to soupify with the onions, just remember to take them out before serving.

                                                        Alternatively you can puree some of the caramelized onions & add it into the soup. Or cut up some of the onions small enough in the first place that they melt into the soup as it cooks.

                                                        1. I totally understand your wanting to follow the original recipe to the letter. It's Julia, after all. To replicate it as closely as possible, I think your best bet is probably almond flour. There's very little almond taste in it to begin with, and in such small quantities it shouldn't alter the taste at all. To me, potato starch makes for a slimier mouth feel, and things like agar agar, cornstarch, kuzu and arrowroot make for an over-slick, glossy, slightly gluey texture, like in old-school Chinese-American restaurant sauces. Almond flour creates a nice toasty roux with no sliminess at all.

                                                          You should look for a product labeled "blanched almond flour", not "almond meal", as that's usually a coarser grind.

                                                          Another possibility that might be easier to find is Bob's Red Mill All-Purpose Gluten-free Flour, which is mostly made of chickpeas.

                                                            1. I sometimes like to thicken onion soup too. I've added flour to the caramelized onions before I add the stock but now that I've discover Xanthan gum, I'd try that. Also, Arrowroot would work well & is GF. I see it all over now that everyone is on GF diets but here's an online source:

                                                              1. I've used a combination of equal parts rice flour, cornstarch and potato flour for thickening sauces and soups. Not everyone likes the rice flour texture, though; it can be a bit gritty.

                                                                1. Lots of ingredients will act as a laxative in certain individuals, like the cheese that is to be used to top the soup.

                                                                  1. You probably made the soup already, but how about a beaten egg or two? File powder might be interesting.

                                                                    1. wekick,

                                                                      There's a huge issue here that I think is being ignored, but I think will more accurately address your problem.

                                                                      It's important to remember the cultural context in which Julia developed these recipes.

                                                                      Who is Julia's intended audience? Remember, Julia is *not* teaching French housewives how to cook.

                                                                      She is teaching AMERICAN housewives, with 1960's ingredients and expectations, how to cook APPROXIMATIONS of French food with American ingredients.

                                                                      Do you think if Julia were instructing French housewives, that she would be instructing them to add flour? I don't think so, and here's why.

                                                                      A French home cook in the 1960's would probably have cooked this soup with a rich homemade beef stock with some meat and lots of bones, which would give off natural gelatin. The meat adds flavor, and the gelatin adds body and richness to the soup.

                                                                      Her American 1960's counterpart would likely be using processed foods-- salty powdered mixes, or flavorless, watery canned broth. (She says this outright in the French Chef episode I linked to elsewhere in this thread, even going so far as to say "there are some very good powdered onion soup mixes on the market, which you can fix up yourself." Hm.)

                                                                      So, I think Julia's addition of butter-toasted flour as a flavorful thickener is really an attempt to help the American home cook to (very) crudely approximate the flavor and texture of what the French home cook would already have.

                                                                      With this in mind, my advice to you is twofold, in descending order of preference:

                                                                      * Make your own rich homemade beef stock and use that for the recipe. Omit the flour (or any thickener) entirely, as the gelatin in the soup will naturally add the body to the soup that the flour would be attempting to simulate. (see recipe below for rich beef stock)


                                                                      * Use a high quality boxed stock and add rehydrated unflavored powdered gelatin to it. It won't improve the flavor of a boxed stock, but this is a very good trick to quickly add body to a thin soup. You could try simmering some minced beef, red wine and bay leaves in the boxed stock, in an attempt to boost the flavor of the limp boxed stock. If this is the case, after enriching the boxed stock, strain out the solids and stir in the rehydrated gelatin towards the end of simmering (gelatin loses its body if you cook it for too long).

                                                                      The French Onion Soup recipe I linked to earlier was engineered to use a supermarket boxed stock, but remember that this is a FAR inferior alternative to using a high quality homemade stock in the first place.

                                                                      Beef stock recipe to follow.

                                                                      Mr Taster

                                                                      Rich Beef Stock
                                                                      Red wine, used to deglaze the pan after browning the beef, adds an extra layer of flavor. To extract maximum flavor and body from the meat and bones, beef stock must be simmered much longer than chicken stock. The stock can be refrigerated in an airtight container for up to 4 days or frozen for 4 to 6 months.


                                                                      2 tablespoons vegetable oil
                                                                      1 large onion, chopped medium
                                                                      6 pounds beef shanks, meat cut from bone in large chunks, or 4 pounds beef chuck, cut into 3-inch chunks, and 2 pounds small marrowbones
                                                                      1/2 cup dry red wine
                                                                      2 quarts water (boiling)
                                                                      1/2 teaspoon table salt
                                                                      2 bay leaves

                                                                      1. Heat 1 tablespoon oil in large stockpot or Dutch oven over medium-high heat until shimmering but not smoking; add onion and cook, stirring occasionally, until slightly softened, 2 to 3 minutes. Transfer to large bowl.

                                                                      2. Brown meat and bones on all sides in 3 or 4 batches, about 5 minutes per batch, adding remaining oil to pot as necessary; do not overcrowd pot. Transfer browned meat and bones to bowl with onion. Add wine to empty pot; cook, scraping up browned bits with wooden spoon, until wine is reduced to about 3 tablespoons, about 2 minutes. Return browned beef and onion to pot, reduce heat to low, cover, and sweat until meat releases juices, about 20 minutes. Increase heat to high, add boiling water, salt, and bay leaves; bring to boil, then reduce heat to low, cover, and simmer slowly until meat is tender and stock is flavorful, 1 1/2 to 2 hours, skimming foam off surface. Strain and discard bones and onion; reserve meat for another use, if desired.

                                                                      3. Before using, defat stock. After stock has been refrigerated, the fat hardens on the surface and is very easy to remove with a spoon. To defat hot stock, we recommend using a ladle or fat separator.

                                                                      1. If you want to thicken the soup just a touch, I would use a slurry of either cornstarch or arrowroot. Both are GF.

                                                                        1. Since this thread is still going... what about the bread!!? This is what really thickens the soup. Thats why you don't want a thick soup. You want the broth to soak into the cubed bread.

                                                                          3 Replies
                                                                          1. re: daislander

                                                                            not all onion soup is served au gratin. in fact, the better the soup itself is, the better it is to omit the broiler step and just serve the onion soup.

                                                                            (but I usually dip crusty bread into just about any and every soup ;-)

                                                                            1. re: daislander

                                                                              The bread is addressed up thread. I don't have the idea of thickening it so much that it will not be absorbed by the bread. The amount of flour is small.

                                                                            2. I wonder why a question as simple as this requires 74 replies (and counting!)

                                                                              1. Gluten only occurs in the minority of starchy grains -- basically wheat and rye. If you really must add a thickener (something that has little influence on the soup's flavor anyway, just its mouth-feel), there are endless options. Cornstarch, rice flour, arrowroot starch, gelatine -- whatever you have on hand. And it need not be added at a paritcular point ritualistically. Just mix it with a little water and stir it in, preferably early.

                                                                              2. ONIONS break down and contribute their own starch when a soup is slowly cooked! It's not unusual for an onion soup with reasonably generous onions to gel when cold, for that reason, even if it's meatless.

                                                                              9 Replies
                                                                              1. re: eatzalot

                                                                                >> (something that has little influence on the soup's flavor anyway, just its mouth-feel)

                                                                                Excess thickener can dilute the flavor of the soup, so it can in fact impact the flavor.

                                                                                Also, type of thickener is important. They are not all freely interchangeable. Thickeners have different properties, and some are more suited to specific applications than others.

                                                                                If the goal of adding thickener is to most closely simulate the body and texture of a slow cooked beef stock using inferior processed broth, then rehydrated gelatine added towards the end of cooking is the best way to do this. The fact that gelatine is gluten free is merely a bonus.

                                                                                Mr Taster

                                                                                1. re: eatzalot

                                                                                  Just a minor correction- while it's wheat gluten that concerns most folks who are eating GF, other grains have glutens of their own. This often is overlooked because of wheat's primacy as an item of interest. But I believe it's the gradual development of gluten that gives risotto its magic, for example.

                                                                                  The acronym I was taught for common gluten-containing grains is BROWS: Barley, Rice, Oats, Wheat & Spelt.

                                                                                  Rye has elements which act like wheat gluten and should be avoided by anyone with extreme sensitivity (like celiac), but those with lesser reactivity often report that for them it's quite innocuous.

                                                                                  1. re: eclecticsynergy

                                                                                    Thanks eclectic. Another aspect of this is that other starch sources than wheat flour, such as cornstarch or arrowroot starch, are deliberately refined to contain essentially just the starch part of the grain, which is what you want for a thickener anyway.

                                                                                    Although wheat flour is often specified in thickening roles in recipes (I believe, after a lot of exposure to such writing, that the basic reason for that is wheat's common availability in Western-culture kitchens, from its use in breads etc), Escoffier in laying out the French cooking canon did stress that in thickening roles the real point is starch (or its modified, cooked form --dextrin), and that flour as a less-pure starch is not the ideal, its other components just get in the way (to be skimmed off so very patiently in a sauce espagnole or whatever).

                                                                                    1. re: eclecticsynergy

                                                                                      Rice does not contain any glutens that pose a problem for people with celiac disease. Even so-called "glutinous" rice is perfectly safe to eat.

                                                                                      1. re: eclecticsynergy

                                                                                        Rice has no gluten whatsoever. Period. The R is for Rye. It has gluten. not merely elements that act like gluten.

                                                                                        1. re: Karl S

                                                                                          Okay, I must've been misinformed- I was told rye contains something called secalin which, because of a protein they have in common, acts like wheat gluten to those who are highly reactive.

                                                                                          I also didn't know that rice doesn't have any glutens of its own.

                                                                                          The point of my post was that other grain glutens, like the ones in oats, are often forgotten because the folks who have to avoid wheat gluten generally don't need to worry about these other ones. At least that was my understanding; I don't claim to be an authority on the subject.

                                                                                          1. re: eclecticsynergy

                                                                                            Oats can be problematic as well. Back in the dark ages, when I was diagnosed, celiac patients were advised to avoid oats. Turns out there are two separate issues with them. They don't contain gluten, but they contain avenin, and some patients will react to that, others will not. The other problem, which is of more concern to most of us, is that tests on oats have shown them to be highly "contaminated" with wheat, due to crop rotation, shared storage facilities, etc. This is enough of a problem that standard oats are not safe for someone with celiac disease. There are companies now growing "gluten-free oats" under controlled conditions, in fields where wheat is never grown. Most people with celiac disease can tolerate these (I can), but there seems to be a subset that cannot.

                                                                                            1. re: eclecticsynergy

                                                                                              Gluten is an umbrella term for the prolamine proteins gliadin (in wheat and its close relatives), secalin (in rye), and hordein (in barley).

                                                                                        2. Everybody assumes the flour is purely for thickening. Maybe it's for an added taste dimension. I think in this case making a roux in the oil that's sauteing the onions might add a mellowness and nuttiness that you won't have otherwise. As I said in my post, I don't think cornstarch, arrowroot, etc will give the soup either the toasty flavor or texture intended.

                                                                                          Also, Chowhounds, why can't we just give original posters what they want instead of always trying to convince them they're wrong for wanting it? I can understand the first few people who suggested wekick shouldn't thicken the soup at all, but after she explained her reasoning and preference, couldn't we just honor her request?

                                                                                          8 Replies
                                                                                          1. re: ninrn

                                                                                            >> Everybody assumes the flour is purely for thickening

                                                                                            Did you read my posts? I'm part of "everybody" :)


                                                                                            Mr Taster

                                                                                            1. re: Mr Taster

                                                                                              OK, Mr. Taster, your post does acknowledge the flavor contribution of the roux. But, with all manner of fondness and respect for your (and everybody else's) experience and enthusiasm, your post is still basically a tutorial in how to make the base for your preferred version of French onion soup, and an argument as to why the OP shouldn't want to duplicate Julia Child's recipe as it is.

                                                                                              Julia Child fans want to make Julia's recipes exactly as Julia wrote them. It's part of the fun, part of the way one learns from her recipes, and kind of an homage to her and to all the work she put into creating them.

                                                                                            2. re: ninrn

                                                                                              Folks, this isn't Suprêmes de volaille "Alexis Bespaloff," or even risotto Milanese. It's ONION SOUP, a generic folk dish, possibly Europe's original folk dish, and in any case predating written history. Almost any cooking of onions in broth or even water, with seasonings you like, yields a creditable result.

                                                                                              I think Julia Child herself would have discouraged "authenticity" finicking. And Escoffier, whom Julia Child largely just interpreted for US home cooks, stressed much earlier that the point of roux is dextrin, the fat is just a carrier, and purer starches like corn are preferable to flour anyway. In JC's "Mastering" recipe, the flour is clearly just a mild thickener, cooked a few minutes via the in-fat ritual; the onions are first cooked far longer, to brown, then again to finish the soup.

                                                                                              I've made batches of onion soup at home several times a year for 40 years _starting_ with JC's particular recipe, trying endless variations, tasting restaurant versions from Paris to New Orleans. All this fuss is unnecessary, you don't need any thickening fundamentally, and if you do, replacing JC's wheat flour with a little less cornstarch or rice flour would be truer to Escoffier anyway.

                                                                                              1. re: eatzalot


                                                                                                This is not about launching the space shuttle or curing cancer.

                                                                                                It's soup. An an uncomplicated one at that.

                                                                                                Just omit the flour.

                                                                                              2. re: ninrn

                                                                                                did you read the OP???

                                                                                                "for GF onion soup?"

                                                                                                I don't think that any amount of "nuttiness" makes up for flour not being GF.

                                                                                                1. re: Gastronomos

                                                                                                  Gastronomos, C Hamster and eatzalot: Yes, I read the original post and the whole thread. The OP asked for something very specific -- a gluten-free substitute for the 2 tablespoons of wheat flour in a given recipe.

                                                                                                  Some people responded by telling the OP to omit it all together. OK, fine, something to think about.

                                                                                                  But the OP posted again and said she/he'd prefer to substitute the flour with something else and adhere as closely to the recipe as possible.

                                                                                                  A few people (including me) gave the OP some gluten-free suggestions (not all flours contains gluten, Gastronomos, and none of my suggestion do). But most people who posted after the OP's second request continued to go on and on about how thickening the soup with flour is stupid and that she/he is wrong for wanting to adhere to the recipe that closely.

                                                                                                  The gist of my second post is: The OP said what was wanted, then said it again. Why can't we just respect that and stop telling her/him to want something else? This happens on Chowhound all the time and I guess it strikes me as a bit disrespectful, that's all.

                                                                                                  1. re: ninrn

                                                                                                    well, the op is insistent upon "following the recipe", but CANNOT, because it must be gluten-free. lol. it's actually all kinds of funny that this thread is now this long.

                                                                                                    i eat gluten-free for health. my onion soup is silky and rich because of the home-made stock. however, the jc soup recipe in question is not "thick" by any stretch of the imagination and yeah, it's a simple peasant dish -- not rocket science.

                                                                                                    1. re: ninrn

                                                                                                      I tried to follow you, but you lost me from the get go. best of luck to you!

                                                                                                2. Thanks to everyone who commented. When I first posted this I had thought of just leaving the flour out but I was thinking maybe someone on this forum has made this and has a good suggestion about replacing the flour in this particular recipe.

                                                                                                  As to all of the other discussion.
                                                                                                  A substitution might bring me a step closer to that recipe or it might be that nothing will. While I agree with a poster above that much of the best GF food is food that just happens to be GF, that can be very limiting. In order to expand what you can eat, you have to make some substitutions. While I am using this specific recipe this time for the reasons above, catering to my audience, I am looking to add onion soup to my repertoire. I always had this at restaurants because my husband didn't like it, but after 35 years, he decided a few weeks ago that he loves it. Go figure.

                                                                                                  While I was surprised by the strong opinions in this discussion, I think this is useful. The detailed instructions some wrote are the things that move a dish from good to great. I suppose a cooking forum is the place to discuss the nuances of onion soup. It is simple and yet people have some very strong opinions about those simple things and rightly so in my mind. The people who participate on these forums do appreciate what can be subtle differences. I would never demean others for their opinions though. If some have an opinion different from mine, it is what they like, no hand wringing from me. I feel like I always learn something though by listening to what people have to say. I don't feel that my way is the superior way for everyone. Even though i have been cooking for a long time, starting at the knee of my grandmother who cooked from scratch using as much from the farm as possible, I am always considering different ways of doing things even if I think I have a pretty good way of doing it already. In this case, I haven't made onion soup that much but just from my own experience know that a well made stock made by me would be best for that component. I personally have no allegiance to the necessity of flour, in general but this discussion did make me think why one might use flour. Many do, including renouned chef Thomas Keller, along with I'm sure in his case is a stock that is exemplary.
                                                                                                  Flour has the following actions, in my mind, whether or not you think these are good or bad.
                                                                                                  It absorbs what ever fat you are using and allows it to be incorporated into the broth.
                                                                                                  It has a taste that it adds which varies according to how much it is cooked.
                                                                                                  It provides a thickening which is on a continuum of barely perceptible to you can stand a spoon up in it.
                                                                                                  It opacifies what you are cooking.
                                                                                                  I don't think it is a matter of right or wrong but personal preference.
                                                                                                  Ill play it by ear with this batch. I have to make two batches so I'll do one with flour and see how the one without, is. I will have a couple of alternative things to add if need be but if you can't replicate the properties of flour that you want by substitutions then I would leave it out.

                                                                                                  One thing I have noticed with restaurant onion soup is that it is often too salty. I think this can be from canned broth, salting early and too much reducing or from sitting finished, hot and evaporating though the day.

                                                                                                  1 Reply
                                                                                                  1. re: wekick

                                                                                                    "One thing I have noticed with restaurant onion soup is that it is often too salty."

                                                                                                    Yes, and that applies to many restaurant foods -- but specifically soups and for prescisely the several reasons you mentioned. (Salt, and its flavored variants such as "broth bases," are among the classic crutches that prop up flavor in broths weak on fundamental quality ingredients.)

                                                                                                    I cook soups, incl. onion soups, a lot and I think you are on exactly the right track. A good stock is the soul of good onion soup.

                                                                                                    And for the record, JC's presentation of this dish is sort of the basic French recipe found in standard French cookbooks (I just checked in Escoffier, 1921, and Mme. Saint-Ange, 1927). But French tradition itself has all sort of variations. No flour; cooked soup rubbed through a sieve for a smooth puree; "Lenten" versions using water or vegetable stock instead of meat broth. (I already mentioned that Escoffier himself even explicitly favored alternatives to flour, such as cornstarch -- a century ago -- but usually listed flour, simply for being most commonly available. JC herself was strongly criticized in the 1970s in fact for leaning harder on flour and thickenings in general than did Escoffier on whose recipes her own are based.)

                                                                                                    But when you make soup yourself, you can try anything you want and find what works for YOU. "Now you are really cooking!" (Julia Child, FJCC, 1975.)

                                                                                                  2. You can use gf all purpose flour or a little corn starch. If you are using corn starch, use it sparingly. You want very little thickness in the soup, you don't want it to get thick. Just sprinkle it in as you stir or else it will lump up.