Stir curd and milk until smooth. Cut the vanilla pod lengthwise and scrape out the pulp. Add vanilla pulp and lemon juice to the quark and mix. Season to taste with a few drops of sweetener.
Wash the grapes, pluck them from the stems and cut them in half. Wash the mint, dab dry and dust with icing sugar. Layer applesauce and quark in a small bowl. Put grapes on top and decorate with mint.