For the base, cover a springform pan (26 cm Ø) with baking parchment, enclose the rim. Chop the chocolate coating. Melt with butter in a hot water bath. Put the cookies in the freezer bag, close it and crumble them finely with a dough roll.
Mix well with the couverture. Pour into the mould and press down firmly as a base. Chill for about 1 hour.
For the ice cream, roughly chop the almonds and roast them in a pan without fat. Let it cool down. Wash the cherries, remove the stalks and stone them. Stir sauce powder and 6 tbsp cherry nectar until smooth. Bring the rest of the nectar to the boil, thicken with the sauce powder and simmer for about 1 minute.
Fold in the cherries, allow to cool slightly.
Mix quark, mascarpone, sugar and lemon juice. Whip cream until stiff, fold in almonds and compote. Spread on the base. Cover with foil and freeze for at least 6 hours. Let the cake thaw 20 minutes before serving.