Preheat oven to 400°F.
Spray muffin tin with cooking spray.
Mix cereal, banana, milk, egg, and oil in a bowl.
1 1/2 Cups Bran Flakes, 1 Cup Ripe Bananas, 1 Egg Egg, 3 Tbsp Vegetable Oil, 1/2 Cup Fat-Free Milk
Let stand 5 minutes.
In a separate bowl, mix flour, sugar, baking powder, baking soda, and cinnamon.
1 Cup Flour, 1/4 Cup Sugar, 2 Tsp Baking Powder, 1/2 Tsp Baking Soda, 1/4 Tsp Cinnamon
Combine the two mixtures, stirring just until moistened.
Fill each muffin section two-thirds full.
Bake for 20 minutes, or when a toothpick inserted into the center comes out clean.
Let cool and serve.