Stir the fat until it is smooth. Gradually add sugar, vanillin sugar, cinnamon and eggs. Sift the flour and baking powder, mix with the hazelnuts and stir into the fat-sugar egg mixture by the spoonful.
Drain the cherries well (put some aside for decoration) and fold into the dough. Pour the dough into a greased box form (25 cm Ø; 1.75 litres capacity). Bake in a preheated oven (electric: 175 °C/ gas: level 2) for 1 hour.
Take out the cake and let it cool down. Whip the cream until stiff, fill in a piping bag with star-shaped spout and squirt onto the cake. Place the cherries on the cream. Warm up the raspberry jelly and spread over the cherries with a spoon.