Chop 100 g of chocolate and melt over a warm water bath. Cream fat, sugar, salt and vanilla sugar with the whisk of the hand mixer. Stir in the eggs one after the other. Mix flour and baking powder and stir in alternately with the buttermilk.
Halve the dough, stir into one half liquid chocolate and cocoa.
Fill both halves of the dough alternately, spoon by spoon, into a greased, flour-sprinkled ring cake mould (24 cm Ø; 2 litres capacity). Add the following dough to the existing dough.
Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: see manufacturer) for approx. 50 minutes. Remove from the oven and leave to rest in the mould for approx. 15 minutes. Carefully turn out of the tin and let it cool down.
Chop the remaining chocolate. Heat the cream in a small pot. Melt the chocolate while stirring. Let it cool down for about 5 minutes. Cover the cake with the chocolate cream. Put the cake in a cool place for about 30 minutes.
Cut into pieces. Cream tastes good with it.