Preheat the oven to 180°C (356°F).
Mash the banana with a fork.
Mix almond flour, cocoa powder, and baking powder together.
Add eggs, mashed banana, Greek yogurt, and honey, then mix thoroughly.
Pour the batter into a brownie mold.
Bake in the oven at 180°C (356°F) for 20 minutes.
Let it cool before eating.