Baking tip: gluten-free flours do not absorb as much fat as wheat flour
Tis the season for cookies! The delicious buttery, fatty, spirit-boosting goodness that I am obsessed with every year. Everything from classic oatmeal and chocolate chip to window-paned and rollouts. I love cookie season, but I've learned a lot through trial-and-error about the unwritten rules one must keep in mind when using gluten-free flour blends, especially when you mix your own.
I have spent so much time fighting with recipe conversions simply because I didn't know that gluten-free flours don't absorb as much fat as gluten-containing flours. Really, someone should hand out a baking primer with info like this to newly diagnosed patients who have to restrict gluten from their diets. "Oh by the way, here are some handy tips in the kitchen so you'll not break yourself, or your bank account, trying to figure it all out."
1-to-1 blends are a possible exception: the pre-mixed flour blends already contain xanthan gum for binding, but they also tend to have a list of other ingredients that counteract some of the lower fat absorption rate. Even so, I've still found 1-to-1 blends that turn my cookies into greasy crepes.
In addition to reducing the amount of fat in recipes during conversion, the other key tip for cookies: always, always refrigerate for at least an hour. Overnight is even better! The chill time allows the fat firm up again so that when it is time to bake, there's far less spread.
Also, this rule isn't just for gluten-free cookies, as J. KENJI LÓPEZ-ALT from the Food Lab over at Serious Eats concluded with the wonderful article "Step-by-Step: The Food Lab's Ultimate Chocolate Chip Cookies." The information in that piece is so valuable, regardless of whether you're a gluten-containing or a gluten-free baker. When it comes to ensuring a put-together cookie, chill the dough first.
I recommend testing out a basic 1-2-3 ratio cookie (1 part sugar, 2 parts fat, 3 parts flour) with your preferred gluten-free flour and butter, and adding just a pinch of salt for flavoring. This way you can use a much smaller amount of ingredients while playing around to find the sweet spot of flour and butter combination. Once you've established a baseline, then you'll be able to look at other conventional recipes and know by how much to reduce the fat.
I'll post the results of my cookie palooza next week. Happy baking!