2/3 c. butter
2 c. sugar
5 egg whites
3 c. sifted cake flour
3 tsp. baking powder
1/2 c. milk
1/2 c. water
1 1/2 tsp. vanilla

Cream butter, add sugar gradually, and continue creaming until light and fluffy. Add unbeaten egg whites, 1 at a time, beating each in before adding another. Sift flour and baking powder together 3 times and add alternately with milk and water and vanilla. Divide batter into 3 slightly greased 8" cake pans and bake for 25 or 30 minutes at 350 degrees. When cool, frost with any desired frosting.