Combine mix and sugar. Add milk and vanilla and beat until well mixed, by hand or about 2 minutes on medium speed of electric mixer. Add egg and continue beating until well mixed, by hand or about 1 minute on medium speed. Pour batter into an 8 by 8 by 2-inch pan, bottom rubbed with shortening. Bake in a 375 F. oven 25 to 30 minutes. Frost cooled cake with Snowy Orange Icing (see index), if desired. Yield: One 8-inch square cake