01 - Preheat oven to 350°F. Lightly grease two small ramekins or oven-safe baking dish with cooking spray or butter.
02 - In a medium bowl, whisk together rolled oats, cocoa powder, baking powder, and salt until evenly distributed.
03 - In separate bowl, whisk mashed banana, milk, maple syrup, and vanilla extract until smooth and fully incorporated.
04 - Pour wet ingredients into dry ingredients. Stir until just combined, being careful not to overmix. Fold in chocolate chips and nuts if using.
05 - Divide batter evenly between prepared ramekins. Sprinkle additional chocolate chips over tops for extra melty goodness.
06 - Bake for 22-25 minutes until oats are set and tops appear slightly cracked. Center should feel firm but still moist.
07 - Let stand 5 minutes before serving. Enjoy warm, optionally topped with drizzle of milk or dollop of yogurt.