Preheat oven to 350 and line a baking sheet with parchment paper.
Mash bananas in a medium sized bowl.
Stir in oats and mix until combined.
Add the mix-ins of your choice and mix until combined.
Using a 1 inch cookie scoop, drop dough onto your prepared baking sheets. Use your fingers to gently shape the cookies, flattening them slightly.
Bake for 12 minutes. Let cool for 5 minutes before removing from the pan. Enjoy!