Preheat the oven to 350 degrees Fahrenheit.
In a large mixing bowl, whisk together the oat flour, quick oats, baking powder, baking soda, salt and cinnamon. Set aside.
In a second bowl, add the bananas and mash really well.
Once mashed, whisk in the egg, almond butter, vanilla and maple syrup.
Add the dry ingredients to the wet and mix together with a wooden spoon.
Fold in the chocolate chips or nuts if using.
Use a cookie scoop to form the cookies and add to a baking sheet lined with parchment paper.
They won't spread much while baking, so press down slightly with your fingers to form the shape you want. The dough will be sticky, so it helps if your fingertips are slightly wet.
Bake for 8-12 minutes. The edges should be golden brown and the center should still feel soft. The will continue to firm as they cool.