Drop 24 heaping tablespoons of dough 2 inches apart onto cookie sheets. Press thumb into center of each cookie to make indentation, but do not press all the way to the cookie sheet (if dough sticks to thumb, spray thumb with cooking spray). Bake 9 to 11 minutes or until almost no indentation remains when touched. Cool 1 minute; remove from cookie sheets to cooling rack. Cool completely, about 20 minutes.