Preheat oven to 350. In a large mixing bowl, combine bananas, peanut butter, and egg.
Add oats, chia seeds, baking powder, vanilla, and cinnamon. Stir to combine. Fold in chocolate chips.
Line baking sheet with parchment paper. Using a medium cookie scoop, scoop dough to form about 10-12 cookies. Flatten the top of each cookie and bake for 22-25 minutes.
Allow cookies to cool on baking sheet before serving.