Preheat the oven to 170 degrees Celsius.
In a bowl, mash the banana.
Add in the cocoa powder and peanut butter, and mix well.
Pour into a ramekin dish and bake in the oven for 15 minutes. To save time, you can microwave for about 90 seconds instead (way nicer baked so def worth the wait).
Serve hot out of the oven.
Add in some mix ins before baking if you want to try out some different flavours e.g. berries, nuts, chocolate chips etc.