Set the oven to 160 degrees circulating air or 180 degrees top / bottom heat.
Mix the flour, sugar, vanilla sugar, cocoa powder, cinnamon, baking soda and baking powder together. Add the egg, milk, cream, maple syrup, butter and bananas and mix everything well. Pour the batter into muffin molds or on a baking tray and bake for 25-30 minutes. Let cool down.