Beat egg whites at high speed until foamy. Add milk and margarine; beat at medium speed until well blended. Gradually add bread flour, whole wheat flour and salt, beating until mixture is smooth.
Coat muffin pans with cooking spray. Heat at 230ºC or 2-3 minutes or until hot. Remove pans from oven. Pour 1 tablespoon batter into each cup; sprinkle each with 1 teaspoon cheese. Fill cups three-fourths full with remaining batter. Bake at 190ºC or 45 minutes.
(70 calories each/27 percent from fat) Fat: 2.1 g (0.5 is saturated fat)