Soak gelatine in cold water. Chop 60 g dark chocolate. Melt butter and chocolate in a pot. Remove from the heat and allow to cool slightly. Put the biscuits into a freezer bag and crumble them finely with a dough roll. Mix cookie crumbs and chocolate butter well. Grease a springform pan (26 cm Ø) with oil. Pour the crumbs into the bottom of the springform pan and press them down firmly to a smooth base. Refrigerate the base for about 30 minutes.
Whip 200 g cream with the whisks of the hand mixer until stiff. Bring 100 g cream to the boil in a small pot, dissolve 200 g dark chocolate in it. Squeeze the gelatine well and dissolve in the cream as well. Stir quark, mascarpone and sugar until smooth. Stir the chocolate cream into the cream, fold in the whipped cream
Fill the cream into the mould and smooth it down. Chill for about 2 hours. Wash and clean the strawberries, dab dry and cut in half. Chop white chocolate and dissolve over a warm water bath. Remove the cake from the mould, spread the strawberries on the cake with the cut surface facing down. Bring jam to the boil with 1 tbsp. water and brush the strawberries with it. Spread the chocolate with a teaspoon over the strawberries. Chill again for another 20 minutes
waiting time approx. 2 1/4 hours