Start the oven with electrical heat at 180 degrees Celsius.
Chop the chocolate in pieces.
Make the bananas in to puree.
Whip the sugar, vanilla sugar and eggs very fluffy.
Melt the margarine and pour it in the batter together with baking powder,flour, cacao powder and the milk. Stir it all together.
Place small muffin forms on a baking sheet and pour the batter in the forms. Pour the chocolate bites on top of the muffins.
Place the muffins in the middle of the oven for ten minutes. Take them out and let them cool down a few minutes before serving them.