How to turn a cake recipe into a cake-cookie recipe?
I basically agree with HalfPint, as whatever we recommend here is entirely empirical and will not have been tested. But i actually love challenges like this, so if you dont mind risking having to ditch ingredients, Im willing to take this on. For guidance, I turned to Michael Ruhlman's wonderful book Ratio which, if this is something you like to do, is super helpful in understanding how to build recipes. According to Michael, a quick bread is (by weight) 2 parts flour, 2 parts liquid, 1 part egg and 1 part fat. (In this case, the mashed banana also serves as the liquid.) A cookie is 1 part sugar, 2 parts fat, and 3 parts flour. No liquid. There is also a wonderful book, Bakewise, by Shirley Corriher, that helps explain the science of these ingredients. It seems to me that the big issue with this recipe is going to be how to get everything to hold together. You'll know after it's mixed whether it can be scooped into cookies. To set yourself up for success, use high protein flour (bread flour if you have it). If not, you might have to add another 1/4 cup of four to your dough to make it scoopable. We're also going to let the dough sit in the refrigerator for a few hours to firm up before scooping into cookies. Here goes: