Preheat your oven to 375°F (190°C) and spray a casserole dish with cooking spray.

In a large mixing bowl, combine the rolled oats, milk, eggs, cinnamon, baking powder, and vanilla extract. Stir until just combined.

Slice one ripe banana and arrange the pieces at the bottom of the prepared casserole dish.

Pour the oatmeal mixture over the layers of banana in the dish and spread it evenly.

Slice another banana and place the pieces on top of the oatmeal mixture. Drizzle or dot with peanut butter.

Sprinkle chocolate chips on the top if desired.

Bake in the preheated oven for 25-30 minutes until golden and set.

Let it cool for a few moments before serving warm.