1. Heat oven to 375 degrees F. Spray bottoms of 12 standard muffin cups.Lemon-Sugar Topping:
2. In small bowl, mix sugar and lemon zest.Muffins:
3. In another small bowl, combine blueberries and 1 tablespoon flour; toss to coat blueberries. In large bowl, whisk together remaining flour, baking powder, baking soda and salt.
4. In medium-size bowl, whisk egg whites, yogurt, milk, applesauce, sugar, lemon zest and vanilla; stir in blueberries. Make a well in flour mixture; pour in egg white mixture. Stir just until dry ingredients are moistened.
5. Spoon 1/4 cup batter into each cup. Sprinkle 1 teaspoon Topping on each. Bake in 375 degree F oven for 20 minutes or until toothpick comes out clean.
6. Cool pan on rack 5 minutes. Remove muffins; cool on rack. Makes 12 standard muffins.