4 slightly beaten egg whites
1 1/2 cups sugar
1 1/2 tablespoons margarine
2 teaspoons vanilla
2 cups nonfat sour cream
3 cups flour
4 teaspoons baking powder
1 teaspoons baking soda
1 1/2 teaspoons salt
2 cups blueberries

Topping:
1/2 cup brown sugar
1 1/2 teaspoons cinnamon
2 teaspoons melted margarine

Combine egg whites, sugar, margarine, vanilla and lowfat sour cream and mix well. In separate bowl, combine flour, baking powder, baking soda, and salt and mix well. Gradually add flour mixture to batter. Pour half of batter into a 9 x 13-greased pan, top with blueberries and then add the rest of batter. Combine topping ingredients and sprinkle over all. Bake at 350 degrees for 40 to 50 minutes. Cut into 16 squares.

Makes 16 Servings
Serving Size: 1 piece