Combine both flours, oats, brown sugar, baking powder, baking soda, salt, & cinnamon in a bowl. Set aside. Whisk together the egg, milk, applesauce, & vanilla extract. Add the mashed banana & combine thoroughly. Stir in the flour mixture. Scoop the batter into a mini muffin pan. Bake for 8-10 minutes. Cool on a wire rack. So cute served or given as a gift in a recycled egg container!