Beat the quark with a whisk and a dash of milk until it is smooth. If necessary, add yoghurt if not enough
Whip the cream and add to the quark mixture. Stir in a little sugar to taste. 100 g more or less does not matter in principle, you just shouldn't over-sweeten the quark mixture and the raspberry sauce.
Put the raspberries with sugar in a bowl to taste, if possible let them steep in the fridge overnight, then add a little yoghurt so that there is no ice-water slash .. They can also be thawed frozen raspberries, by the way
Now as you like, either separately from each other or together in the ice cream machine. About 30-50 minutes, and then enjoy as a sorbet or ice cream ...