Wash the bananas, peel them, and cut into smaller pieces. For this recipe, it’s best to use very ripe bananas as they are naturally sweeter. Place the bananas, cocoa powder, and walnuts in a tall container, such as a blender cup, and blend until smooth.

Preheat the oven to 180°C (356°F). Transfer the prepared mixture into a small baking dish lined with parchment paper or lightly greased. Smooth the top and bake for about 15-20 minutes, depending on your preferred level of doneness. After baking, remove from the oven and let it cool slightly.

Sprinkle the cake with coconut flakes. Enjoy warm or cold.