PREHEAT oven to 350°F. Beat cream cheese and 1/2 cup of the sugar in large bowl with electric mixer on medium speed until well blended. Add egg whites and lemon peel; mix well. Mix together 1 cup of the flour and baking soda. Stir into cream cheese mixture alternately with sour cream, mixing well after each addition. (Do not over mix.)

SPRAY a 9-inch springform pan with cooking spray; spread cream cheese mixture onto bottom and 1 inch up side of pan. Toss 2 cups of the berries with remaining 1/4 cup sugar and remaining 2 tsp. flour; spoon over cream cheese mixture in pan to within 1/2 inch of edge.

BAKE 40 to 45 min. or until toothpick inserted in centre comes out clean. Cool 10 min. before removing rim of pan. Top with the remaining 1 cup berries. Top each serving with 1 Tbsp. whipped topping.