No. of servings
1. Making a wet mixture
Whisk the egg. Add sugar, vannila sugar, oil and yogurt. Mix it.
2. Making dry mixture
Add the fine flour, baking powder and cocoa. Mix it.
Add pieces of chocolate and sliced banana to the dough.
Put muffin cups into muffin tray. Put dough with teaspoon into each cup. Bake for 20 min at 355°F (180°C).