Old Fashioned Shortbread Cookie
["1 c. butter", "3/4 c. sifted powdered sugar", "1/4 c. cornstarch", "1 3/4 c. all-purpose flour"]
["Cream butter; gradually add powdered sugar and cornstarch, beating at medium speed of electric mixer until light and fluffy. Stir in flour.", "Firmly press dough in lightly greased and floured 9-inch cookie mold.", "Bake at 325\u00b0 for 30 to 35 minutes.", "Invert cookie from pan and let cool on rack."]
["butter", "powdered sugar", "cornstarch", "flour"]