How to make thin crispy oatmeal cookies?
I followed the standard oatmeal cookie recipe... 2 sticks butter, 2 cups flour, 2 cups oats etc. I've made it a dozen times and they're always good. But a few batches ago the dough came out runny and when I put it into the oven it spread like you wouldn't believe. Those cookies came out super-thin, crispy and delicious, and everyone adored them. I've tried to replicate it twice since then and I've just got regular oatmeal cookies... what is the magic formula that changed the cookies???? I'd love to be able to make them that way deliberately!
Melt the butter. Use bleached AP flour, which is usually lower in protein than regular AP.
Use 2-3 Tbsp corn syrup and decrease the sugar by that amount. Add 1-2 Tbsp water to your batter.
Usually, since the pans are hot and the dough warmer, because it has been sitting out, subsequent batches of cookies spread more than the first batch of a baking session. That may have made a difference in your case, or perhaps the thin cookies were from different flour. White sugar makes crisper cookies than brown, but brown sugar gives a deeper flavor. I make very crisp oatmeal cookies, using half of each, and whole wheat flour. I think the melted butter, water, and corn syrup are the key factors. I flatten them with a fork before baking at 375.
sugar could be it.
also, was the butter more melted when you started? did the batter sit out a bit before you baked it. you might try letting it sit for 20 minutes after you're done out of the fridge.
was the weather any different that day? where do you live? the dryness or humidity can always have an impact.