Fruit Crumbles and Crisps toppings turn soggy if made ahead
I love making fruit crisps and crumbles (full disclosure: I have no idea what the differences are between them) all year round with whatever fruits are in season.
They always come out delicious when fresh, and the streusel toppings (again, I don't know what makes something a streusel rather than a crisp or crumble) are nice and crispy and browned.
However, if I make them ahead to time, to bring to someone's house, or to serve hours later, the topping inevitable becomes soft and soggy.
Is there anything to be done? If reheating would help, how long would it need to be in the oven and at what temperature?
If you're starting at room temp, 12 to 15 minutes in a 350F oven should do it. The underside of the topping will still be a little soggy, but the majority of it should crisp up nicely.
"THE irony of a fruit crisp is that it’s usually not, nor is a fruit crumble necessarily crumbly. Most crisps and crumbles (two names for essentially the same thing) are squishy and jammy, with a luscious fruity cushion beneath a shaggy brown-sugar blanket that might contain a few nuts, with or without oats, as a vague attempt at crunch."
~~ Melissa Clark, in the New York Times article, "A Crisp, Made Truly Crisp" (free access):
She sets out to make a truly crispy crisp, and succeeds after a few experiments:
"The crumbs were as crisp as cookies, offering, a textural contrast to the pudding-like berries. It was at once crispy, crumbly and profoundly fruity."
Here's the paraphrase on the recipe
FOR CRUMBLY TOPPING:
1 3/4 cups all-purpose flour
1/3 cup dark brown sugar
1/3 cup granulated sugar
1 teaspoon ground cinnamon
1/2 teaspoon ground ginger
1/8 teaspoon salt
1/2 cup melted butter
1/2 cup finely chopped almonds.
Combine together, makes sure "crumbs" are 1/4" - 1/2". Spread over 9" x 9" pan of fruit. Bake at 350 til bubbly topping is light brown, about 50-55 minutes.
I would try making the fruit part as normal, making the the topping and putting the topping in a separate container. Then when you want to serve it just apply the topping and bake as normal.
If I were to want to serve it where there would be no oven available I would bake the fruit and topping in separate dishes (or maybe with 1/3 of the topping on the fruit to prevent it drying out or going odd). Then later adding the pre-cooked crumble topping to the fruit and serving.
If you do try either of those ideas please let us know how they turned out.
I find that crumbles/crisps (I don't know the difference either!) hold up better with a more cookie-like topping. That means look for a recipe where you are actually making a dough and sprinkling it onto the fruit, instead of just rubbing butter into flour and sugar for a typical crumb topping. I used Smitten Kitchen's peach and pecan sandy crumble recipe this week and it held up great for two days! Her recipe calls for melting butter and mixing it with the sugar, flour, etc.
This sounds like a fabulous idea/recipe - I'll have to give it a try next time I make a crumble.
I have made a couple recently and was able to get the top nicely crunchy (it takes a LOT longer than you might think, though - I went almost an hour at 400, the same as I would for a pie), but the underside of the topping was still gummy and I felt like it was keeping the fruit from cooking thoroughly in the middle. Next time, I was planning to bake the topping separate from the fruit for 30 mins and then add it for the last 15 or whatever, but the Smitten Kitchen recipe might work even better.
One thing that will help is to not cover it until it is completely cool if it has to travel since risidual heat will steam the topping when trapped under a cover. I don't cover it at all if doing it at home the same day.