01 - Preheat oven to 350°F. Lightly grease two small ramekins or an oven-safe baking dish with cooking spray or a small amount of oil.
02 - In a medium bowl, whisk together rolled oats, cocoa powder, baking powder, and salt until evenly distributed.
03 - In a separate bowl, mash the ripe banana thoroughly. Whisk in milk, maple syrup (or honey), and vanilla extract until smooth and well combined.
04 - Pour the wet ingredients into the dry ingredients. Stir until just combined, being careful not to overmix. Gently fold in chocolate chips and nuts if using.
05 - Divide the batter evenly between the prepared ramekins. Sprinkle additional chocolate chips over the tops for extra texture and visual appeal.
06 - Bake for 22 to 25 minutes until the oats are set and the tops appear slightly cracked. A toothpick inserted into the center should come out mostly clean.
07 - Let the baked oats cool for 5 minutes before serving. Enjoy warm, optionally topped with a drizzle of milk or a dollop of yogurt.