2 cups all-purpose flour
1 1⁄2 cups sugar
1⁄2 cup cold butter or 1⁄2 cup margarine
1 teaspoon baking powder
1 cup milk
2 eggs, separated
2 cups blueberries, fresh or frozen (If using frozen, do not thaw before adding to the batter)
In a mixing bowl, combine flour and sugar.
Cut in butter until crumbly.
Set aside 3/4 cup for topping.
Add the baking powder, milk and egg yolks to remaining mixture; mix well.
Beat egg whites until soft peaks form; fold into batter.
Pour into a greased 13″ x 9″ x 2″ baking dish.
Sprinkle with blueberries and reserved crumb mixture.
Bake at 350 degrees for 30-35 minutes or until golden brown and a toothpick inserted near the center comes out clean.
Source : allrecipes.com