Help with gluten-free, vegan substitutions in a cake recipe

My son is allergic to wheat, egg, and dairy, and I'm still learning. I made the Smitten Kitchen summer strawberry cake recipe the other day with gluten free flour, soy milk, earth balance, and came out of the oven beautifully but by the time I served it the next day it had basically turned into soup. I've used these substitutions in other recipes with greater success...was it too wet from the strawberries? Should I have cooked it longer? Do you have any tips? The strawberry cake soup was delicious, but required a lot of explanation when I served it to my skeptical colleagues at work...



Andreea June 18, 2016
Coincidentally I made this recipe the other day. I subbed the butter for dairy free baking spread and the egg with a flax egg + 1/2 teaspoon of baking powder. I haven't really had positive experiences with aquafaba as egg replacer in anything expect meringues because it's very wet so I think you might try baking the cake again with flax instead of aquafaba. My cake turned out pretty much how the one on the blog looks though it tasted a bit bland, perhaps because I didn't have any barley flour and just used all-purpose. You do have to bake it for a really long time (over an hour) until the dough in the centre springs back when you touch it.

I also think the cake is best eaten hot straight out of the oven because to me large fruit baked into cakes like this tastes slimy and mushy once it goes cold.
allyeats June 20, 2016
Thanks for your reply! I almost always use flaxseed but thought the aquafaba might result in a cleaner looking and tasting cake. I've tried aquafaba a few times and haven't had much luck. Everybody says it's the greatest thing ever, but I'm still not convinced....haven't tried meringues yet, though.
Nancy June 17, 2016
I can help more with replacements for egg & cow milk.
In baking I've found that soft tofu can replace egg, volume for volume. Buzz it in a blender or processor with other wet ingredients and it works beautifully. But the "soft" is important...not a brand name, but a texture, and firmer textured tofu won't work as well.
For milk replacement, I prefer the flavor of nut milks, especially almond and cashew to others (rice, soy milk).
For fat, there are loads of cake recipes that successfully use vegetable oil or olive oil. I wouldn't use them as 1:1 replacements for butter, bc fat and water percentages are different, and some flavors don't mix as well. But still, good to know.
For flour, I've not had a lot of taste or texture success with GF flour, but hear good things about this one:
Nancy June 17, 2016
Specific response to your questions about this recipe

The dessert looks more like a clafouti (pastry barely held together with fruit).
Also from the proportions of ingredients & Deb Perelman's comments, even regular flour has trouble holding that much (4c or 1lb) fruit together. So, by analogy, the GF flour, which has less structure, would have even more trouble.

Yes, I think your analysis of too many strawberries is right. And no, cooking it longer probably wouldn't help. Rather, if you like the taste enough to make again, reduce the volume of fruit and plan on eating it day of baking.
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