In large bowl, combine cereal and buttermilk; let stand 5 minutes until cereal is softened. Add applesauce, oil and egg whites; blend well. Lightly spoon flour into measuring cup; level off. Stir in all purpose flour, whole wheat flour and remaining ingredients; mix well. Batter can be baked immediately or stored in tightly covered container in refrigerator for up to 1 week. When ready to bake, heat oven to 400°F. Spray desired number of muffin cups with nonstick cooking spray or line with paper baking cups. Stir batter; fill spray-coated muffin cups 3/4 full. Sprinkle with sugar, if desired. Bake at 400°F. for 15 to 20 minutes until toothpick inserted in center comes out clean. 30 muffins. TIP: To substitute for buttermilk, use 4-1/2 teaspoons vinegar or lemon juice plus skim milk to make 1/2 cups. Nutrition information per 1 muffin: calories 120 (29% calories from fat), protein 3 g, carbohydrate 21 g, fat 4 g, cholesterol 0 mg, sodium 125 mg, potassium 115 mg, dietary fiber 3 g, bake 44