10-12 large egg whites
1 1/2 Cups sifted powdered sugar
1 Cup sifted flour
1 1/2 tsp cream of tartar
1 tsp vanilla
1 cup sugar

Bring the egg whites to room tomperature. Sift the powdered sugar and flour together several times. In a large bowl, beat the egg whites, cream of tartar and vanilla until smooth peaks form. Gradually add the sugar, and beating until still peaks form.

Gently sift about a quarter of the flour mixture over the beaten egg whites, and fold in. Repeat adding a quarter of the flour mixture at a time.

Pour into an ungreased 10-inch tube pan and bake on the lowest rack at 350°F for 40 - 45 minutes, or until the top springs back lightly when touched. Immediately invert the cake, leaving the cake in the pan, and cool thoroughly. Loosen the sides of the cake from the pan, remove the cake.

For variation, a tsp of mint extract can be used in place of the vanilla and 1 cup of finely chopped mint leaves can be added.