Mix flour and baking powder, add sugar, sifted cocoa, oil, water and vanilla sugar and stir well. Put in a greased springform pan and bake at 180 ° C for about 40 minutes.
After the cake has cooled down, melt the chocolate together with the margarine in a water bath and after a short cooling, distribute it evenly on the cake.
Tip:
Divide the dough for a marble cake, put 20 g cocoa under one half. Put both in the mold one after the other and mix gently with a fork.