Psst... We're working on the next generation of Chowhound! View >
HOME > Chowhound > Home Cooking >
Nov 10, 2009 09:39 PM

Help with homemade potato soup that is too thin!

My 86 year old father makes a wonderful potato soup, but this time, he got it way too thin. What can I do to thicken the soup? I've read about roux (?), and several ways to make it. My mom and I had always just used a medium thick mixture of milk and flour, and slowly added the cold mixture to the boiling food.

Anyway, a few suggestions please. There are about 3 gallons of soup. As potatoes tend to disappear after too much cooking, I am wondering if I should strain the soup, and only boil the liquid part of the soup to thicken it?

How much of this "thickener/roux" should I make up, for that amount of liquid/soup? And, I would appreciate a good recipe for the thickener/roux.

I think that is all for now. Thank you so much!
the village idiot

  1. Click to Upload a photo (10 MB limit)
  1. betty crocker instant potatoes with roasted garlic (or "potato buds," which are less expensive but essentially the same thing, without flavoring) -- just stir some in, let incorporate and hydrate completely; repeat this until the soup is thick to your taste.

    3 Replies
    1. re: alkapal

      I'm not really a fan of instant potatoes but I think alkapal's idea is probably the easiest way to thicken this soup, especially in this quantity, without losing flavor; plus it's a really quick fix.

      Roux is a mixture of flour and fat, usually butter, in equal proportions, that has been whisked together and cooked briefly to gelatinize the flour grains. For medium thickness, the ratio is 2Tbsp fat/flour per one cup liquid. You've got 48 cups of liquid,
      you do the math;-).
      The flour/water mix you mentions is referred to as a slurry and is not the best example of a thickener.
      You could certainly strain out the liquid and add it to a roux to thicken but that's lots of extra juggling at this point. In the future, if you want to thicken your soup witha roux, make it (the roux) in advance and add it to the hot soup until you get the desired degree of thickness.
      You have other options for thickening; use heavy cream instead of milk, use a cornstarch slurry (made with milk or stock) or mash some of the well cooked potatoes into the soup.

      1. re: bushwickgirl

        I'm not a fan of instant potatoes either.

        Roux, as mentioned, will require the potatoes to be separated out (by the time the roux has been cooked, the potatoes will be mush). The starch in roux will also naturally hide whatever flavor there is the soup.

        If it were me and the soup was flavorful, but thin, I might add some processed stale bread.

        If the soup wasn't all that flavorful and I felt that the extra starch or potato would mask it too much, I might reach for other ingredients. Ground beef, simmered in a little water, drained, and then toasted for a bit in the oven, will absorb some liquid from soup while giving you another layer of flavor. Same for pork breakfast sausage. The trick is to spread it thinly on a cookie sheet and bake it for a while at a low temp so it really dries out.

        1. re: scott123

          if you used a roux, you'd make it separately, then add it to the soup.
          also remember that the longer you cook a roux, the lesser is its thickening power.
          i think the roux will not help the flavor much, even though it will thicken the soup.

          those betty crocker roasted garlic instant potatoes are quite good. idahoan instant potatoes are good, too. i've seen jacques pepin use instant mashed potatoes to thicken soup.

          otherwise, if you want to work on it, boil more potatoes in some garlic-seasoned water, then mash and add them to the existing soup.

    2. The original comment has been removed
      1. The replies already given will work and it boils down to personal preference.
        Me? I like the roux method.
        I melt butter (actually margerine...) in a pan and stir in enough flour to get it very thick, but not pasty. I usually add too much flour, but not to worry, adding a bit more butter will smooth it out.
        You'll see, the roux has a lot of thickening power.
        I'll put maybe a half cup of roux into a bowl or measuring cup, add 3 cups of simmering soup (from the pot) into the bowl, stir/whisk to incorporate, then stir this slurry into the simmering pot of soup.
        Repeat (if necessary) until desired thickness is reached.
        I find doing it in stages avoids overthickening.

        1. Why don't you just peel a bunch more potatoes, dine them finely and add to the soup. Puree when done. That's the best, easiest and cheapest way of thickening a potato soup. Alternatively, just boil and puree a bunch of potatoes and stir into finished soup. Simmer until flavours are combined. This seems almost a no brainer to me. You'll want to adjust seasoning, of course, to compensate for additional potatoes.

          1. wow.......... y'all are just the best!!!! I realized why my dad didn't think that it was too thin .... he puts his crushed up cornbread in his.... ewwww.

            Anyway, thanks a lot. As I have no instant potatoes,
            I think I'm gonna try the roux, in my half of the soup. I love your suggestion nyleve!

            I have learned so much from y'all. Thanks again!

            The Village Idiot