Heat oven to 375°F. Spray muffin pan with cooking spray.
Stir egg, milk, oil, banana and bran flakes in medium bowl. Let stand for 10 minutes.
Mix flour, sugar, protein powder, baking soda, cinnamon, and salt in large mixing bowl.
Add wet ingredients to flour mixture; stir until moistened. Mixture will be lumpy. Fold in blueberries. Spoon batter into muffin pan, filling 2/3 full.
Bake for 20 to 25 minutes or until lightly browned.