Superman Swirl Sugar Cookies - 1/2 cup powdered sugar, 1/2 cup granulated sugar, 1 cup shortening, 1 egg, 1/2 tsp vanilla, 1/2 tsp cream of tarter, 1/2 tsp salt, 1 tsp baking powder, 2 1/2 cups flour, 2 Tbs sour cream. Mix all ingredients. Divide dough into 3 parts. Knead in food coloring. Combine equal parts of each color to form a small ball. Roll together with hands to swirl. Press to flatten. Bake at 350F for 10-15 min. Makes 24 cookies.