Lemon-Cream Dessert Cake

1 package 2-layer-size regular lemon cake mix
1 cup water
1/3 cup cooking oil
3 egg whites
2 tablespoons finely shredded lemon peel
3 egg yolks
3 tablespoons lemon juice
Creamy Lemon Frosting
(recipe follows)
1. Grease and flour a 10-inch fluted tube pan. In a large mixing bowl, beat cake mix, water, oil and egg whites with an electric mixer on low speed till moistened. Beat the mixture for 2 minutes on high speed. Stir in the lemon peel. Reserve 2 cups of the batter.
2. In a small mixing bowl, beat egg yolks on high speed for 2 minutes. Add reserved batter and lemon juice; beat till mixture is combined.
3. Layer batters alternately in prepared pan, beginning and ending with yolkless batter. Swirl lightly to marble. Bake in a 350° oven for 45 minutes or till done. Cool for 15 minutes; remove from pan and cool completely.
4. Prepare Creamy Lemon Frosting.
5. To assemble cake, cut cake horizontally into three layers. Spread the Creamy Lemon Frosting between layers. Frost entire cake with remaining frosting. Makes 12 servings.
Creamy Lemon Frosting: In a large mixing bowl, beat 1 cup sifted powdered sugar and one 8 ounce package cream cheese (softened) till smooth. Fold in one 8-ounce container of frozen whipped dessert topping, thawed. In a small bowl, beat one 4-serving-size package instant lemon pudding mix and 1 cup milk for 2 minutes with electric mixer on low speed; stir in 1 tablespoon finely shredded lemon peel. Fold the pudding into the cream cheese mixture.
1