Combine first 5 ingredients in a large bowl; make a well in center of mixture. Combine milk and next 6 ingredients (milk through egg whites); stir well with a whisk. Add to flour mixture, stirring just until moist. Gently stir in blueberries. Spoon batter into 18 muffin cups coated with cooking spray.
Combine 1/4 cup flour and remaining ingredients; sprinkle evenly over batter. Bake at 400° for 18 minutes or until done. Remove from pans immediately; cool on a wire rack.