1Heat oven to 350°F. Place 2 tablespoons butter in 9-inch round cake pan; heat in oven until butter is melted. Sprinkle brown sugar and orange peel over melted butter. Arrange peaches over top; sprinkle with blueberries.
2In small bowl, mix flour, baking powder and salt; set aside.
3In medium bowl, beat 3 tablespoons butter and the granulated sugar with electric mixer on medium speed until creamy. Beat in egg whites, applesauce and vanilla until smooth. Alternately add flour mixture and milk in 2 additions. Spoon batter over fruit mixture in pan; spread evenly.
4Bake 30 to 35 minutes or until toothpick inserted in center comes out clean. Cool 5 minutes. Turn cake upside down onto heatproof serving plate. Serve warm with whipped topping.