Reese's Peanut Butter Cup Sandwich Cookies... Reese's Peanut Butter Cup Sandwich Cookies   Ingredients 1/4 cup (1/2 stick) butter or margarine, softened 1/4 cup shortening 1/2 cup granulated sugar 1/2 cup packed light brown sugar 1 egg(s) 1 cup all purpose flour 1/2 teaspoon baking soda 1/4 teaspoon salt 1 cup quick-cooking oats 1/2 cup