Preheat the oven to 180°C (356°F).
Mash the avocado and banana until smooth.
Add the eggs, cocoa powder, almond flour, protein powder, erythritol, and salt to the mashed ingredients, and mix well.
Add baking powder and mix evenly.
Pour the batter into an oven-safe mold.
Bake in the oven at 180°C (356°F) for 20 minutes.
Remove, let cool, then cut into serving sizes.