Fluffy White Cake

Preparation Arrange oven rack in middle position and preheat oven to 350°F. Butter cake pans and line bottom of each with round of parchment. Butter paper, then dust pans with flour, knocking out excess. In large bowl, whisk together flour, baking powder, and salt. In small bowl, combine milk and vanilla. In bowl of electric mixer fitted with paddle attachment, beat together butter and sugar on moderate speed until light and fluffy, about 5 minutes. Reduce speed to low. Add 1/2 of flour mixture and beat until just combined. Add milk mixture and beat until just combined. Add remaining flour mixture and beat until just combined, then raise speed to moderately high and beat 10 seconds. Transfer to large bowl. In clean bowl of electric mixer fitted with the whisk attachment, beat egg whites until they hold stiff peaks. Fold 1/3 of egg whites into batter to lighten. Gently fold in remaining 2/3 of egg whites until just incorporated. Divide batter between prepared pans and smooth tops. Bake cakes until tops are springy to touch and testers come out clean, about 30 minutes for 6-inch cake, 45 minutes for 9-inch cake, and 60 minutes for 12-inch cake. Cool cakes in pans on racks 30 minutes. Turn out cakes onto racks, peel off parchment, and cool cakes completely. (Cakes may be stored at room temperature, tightly wrapped, 2 days; refrigerated up to 5 days; or frozen, double-wrapped, up to 2 weeks. Do not unwrap before thawing.)

Preparation Arrange oven rack in middle position and preheat oven to 350°F. Butter cake pans and line bottom of each with round of parchment. Butter paper, then dust pans with flour, knocking out excess. In large bowl, whisk together flour, baking powder, and salt. In small bowl, combine milk and vanilla. In bowl of electric mixer fitted with paddle attachment, beat together butter and sugar on moderate speed until light and fluffy, about 5 minutes. Reduce speed to low. Add 1/2 of flour mixture and beat until just combined. Add milk mixture and beat until just combined. Add remaining flour mixture and beat until just combined, then raise speed to moderately high and beat 10 seconds. Transfer to large bowl. In clean bowl of electric mixer fitted with the whisk attachment, beat egg whites until they hold stiff peaks. Fold 1/3 of egg whites into batter to lighten. Gently fold in remaining 2/3 of egg whites until just incorporated. Divide batter between prepared pans and smooth tops. Bake cakes until tops are springy to touch and testers come out clean, about 30 minutes for 6-inch cake, 45 minutes for 9-inch cake, and 60 minutes for 12-inch cake. Cool cakes in pans on racks 30 minutes. Turn out cakes onto racks, peel off parchment, and cool cakes completely. (Cakes may be stored at room temperature, tightly wrapped, 2 days; refrigerated up to 5 days; or frozen, double-wrapped, up to 2 weeks. Do not unwrap before thawing.)