Chill Your Dough Before Baking
The worst thing in the world, if you ask us, is a thin, crunchy cookie (unless that’s your goal, but why would it be?). However, the main reason that cookies flatten out too much during the bake cycle is that they didn’t have time to rest in the refrigerator. Once again, cutting corners might seem tempting, but it will backfire.
If you’re looking for large, thick, and moist cookies, give them time to chill before you shape them and toss them in the oven. You should allow your cookie dough to rest for at least an hour in the refrigerator before you cook them. This will allow the ingredients to firm up so that they spread at a slower pace when baked.