Peanut butter cookies, closeup of a stack and broken pieces on a table
The Butter Method That Chewy Cookie Enthusiasts Need To Know
If you’re a fan of ultra-chewy cookies, opt for melted butter in lieu of cold or room temperature butter. Out of all these butter types, melted butter yields the chewiest cookies.
Butter contains fat and moisture, which contribute to the amount of gluten that develops. It adds moisture to the flour and allows gluten to develop, creating a chewy texture.
This is why you want to avoid softened butter; when mixed with sugar, you must cream them together, which results in the addition of air. This makes cookies light, not chewy.
This technique works especially well for drop dough, though it will work for most standard cookie recipes. To make the cookies even chewier, try adding agave syrup.