Brush the cup cake pan with melted butter or oil. Preheat the oven to 160 °C convection oven.
Sift flour, baking powder, baking soda and cocoa into a mixing bowl. Add sugar, vanilla sugar and all other ingredients and mix briskly with hand mixer until all ingredients are combined.
Immediately pour into the greased baking pan and bake in the hot oven for about 35 – 40 minutes on the middle rack.
Test with a chopstick, if nothing sticks, the cake is ready.
Let it rest in the pan for another 10 minutes.
Turn out onto a cooling rack to cool. Decorate with powdered sugar or chocolate icing.
