1 c. sifted all-purpose flour
1/2 c. sugar
1 1/2 tsp. baking powder
1/4 tsp. salt
4 eggs, separated
1/4 c. vegetable oil
1/4 c. water
1 tsp. vanilla extract
1/2 tsp. cream of tartar
1/2 c. sugar

Combine flour, 1/2 cup sugar, baking powder and salt in small mixing bowl. Make a well in center; add egg yolks, oil and water and vanilla. Beat at high speed 5 minutes or until satin smooth.

Combine egg whites (at room temperature) and cream of tartar in a large mixing bowl. Not made of plastic. Beat until soft peaks form. Add 1/2 cup sugar, 2 tablespoons at a time. Beat about 4 minutes at medium speed until stiff peaks form. Peaks should stand straight up when beaters are lifted.

Pour egg yolk mixture in a thin stream over entire surface of egg whites, gently folding mixture, into whites. Pour batter into ungreased 10" tube pan, spreading batter evenly with spatula.

Bake at 325 degrees for 1 hour or until cake springs back when touched lightly. Remove from oven, invert cake in pan, and cool completely before removing from pan.