3 Ingredient Lemon Cookies: 1 box lemon supreme cake mix 1- 8oz tub cool whip topping, softened 1 egg Preheat oven to 350 degrees. Mix all the ingredients. Dough will be thick and taffy-esque. Drop dough in heaping tablespoons onto a greased cookie sheet. Bake at 350 for 10 minutes. Let cool on the cookie sheet for about 10 minutes. Remove. Eat. Share. Enjoy!