Knead the flour, sugar, baking powder, eggs, butter, nuts, almonds, lemon peel, orange peel, sultanas, gingerbread spices and quark into a dough. Roll out the dough, roll the marzipan and place in the middle of the dough and shape into a stollen. Place the Stollen on a baking tray lined with baking paper and bake at 175 degrees for approx. 70 minutes, then immediately brush with melted butter and dust with icing sugar.