Chop the chocolate and melt it over a warm water bath. Grease a springform pan (26 cm Ø), line the bottom with baking paper. Mix quark, sugar, pudding powder and eggs. Fill half of the mixture into the mould and spread.
Mix the rest of the mixture with liquid chocolate and gingerbread spice. Spread the chocolate mixture over the light-coloured mass in spots, marble with a spoon. Cake in a preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: see
manufacturer) bake for about 40 minutes.
Turn off the oven, remove the edge of the cake from the mould and let it cool in the oven for about 2 hours with the door slightly open. Carefully remove the cake from the tin, remove baking paper. Place the cake on a plate and chill for about 1 hour.
Whip the whipping cream with the whisk of the hand mixer until stiff. Pour cream into a piping bag with a medium star-shaped spout, squirt 16 tuffs onto the cake and decorate with chocolate shavings.