Set the oven to 350°F and prep a muffin tin for 12 muffins.
In a food processor, pulse oats into a coarse flour consistency. Then, combine it with whole-wheat flour, baking powder, baking soda, salt, and cinnamon.
In another bowl, combine the whisked mashed bananas, yogurt, maple syrup, egg, and oil.
Wet and dry should be folded together just until incorporated; if you are using them, add chips or nuts.
Spoon the batter into tins and bake for 15 to 18 minutes until the tops are lightly browned, and when tested with a toothpick it comes out mostly clean.
Cool for five minutes in the tin, then transfer them to a rack so they don't get steamed and soggy.