Heat oven to 375°F. In medium bowl, mix cookie mix, butter, flour and egg until soft dough forms. On lightly floured surface, roll dough 1/4 inch thick. Using 4- to 4 1/2-inch round cutter, cut out 7 rounds. Using 2-inch round cutter, cut and remove center from each round (save centers for rerolling). Cut each ring in half, making 2 curved rainbow shapes from each, for a total of 14. Place on ungreased cookie sheet.