Heat oven to 350°F. In 8- or 9-inch square pan, break up cookie dough. With floured fingers, press dough evenly in pan.
Bake 25 to 30 minutes or until golden brown. Cool completely, about 45 minutes. If desired, frost or decorate using ready-to-spread frosting and sprinkles. Cut into 4 rows by 4 rows. Store tightly covered.