Baking cookies in a muffin pan is one of the best tricks out there. If you've ever had problems with cookies that spread all over your baking sheet, it's impossible here. There's nowhere for the cookies to spread because the dough is contained in the muffin cavity. Another nice thing is that you don't have to chill the dough before baking. I recommend dough chilling with almost all my cookie recipes so they don't spread, but it's not necessary here.