Some cookie recipes produce thin, flat and crispy cookies which are unacceptable if you prefer the puffed, cakey variety. The ingredients and baking methods you use affect the final texture of cookies. Make small changes to your basic cookie recipe to keep them from spreading to flat disks and, instead, produce thick, puffy cookies.
Butter has a lower melting point than shortening. This causes the butter in the cookies to quickly melt in the oven and spread out the cookies. Replace the butter in your cookie recipe with an equal amount of butter-flavored shortening to keep the cookies from spreading.
Cake flour contains less protein than all-purpose flour. The protein in flour binds with liquid in the recipe. Cake flour leaves more of the liquid in the cookies free to turn into steam in the oven. This steam causes the cookies to rise and become puffy and thick as they bake. Replace all-purpose flour in your recipe with an equal amount of cake flour.
Replace baking soda in your recipe with baking powder. Use 1 teaspoon of baking powder per cup of flour in your recipe. Unlike baking soda, which requires an additional acidic ingredient to create a leavening reaction, baking powder already has the acid in it. Baking powder will provide lift for the cookies and speed the time the cookies set in the oven, preventing spread.
Cookies spread when they melt quickly in the oven. Chill the cookie dough for at least one hour in the refrigerator before baking the cookies to prevent this speedy spread. Another way to prevent quick melting is to preheat the oven 25 degrees Fahrenheit higher than the recipe suggests. Just before you put the cookies in the oven, turn it down to the proper temperature. The higher oven temperature will set the exterior of the cookies and keep them from spreading.
References and Resources"The Science of Good Food"; David Joachim, et al.; 2008
"CookWise"; Shirley O. Corriher; 1998
"Good Eats: The Early Years"; Alton Brown; 2009