Line a bowl or a small glass casserole dish (just because of the appearance - you can of course also use any container) with Amarettini and soak it well in Amaretto. Beat the cream with the cream stiffener. Mix the quark, crème fraiche, vanilla sugar and lemon juice. Then fold in the cream.
Pour part of the quark mixture into the mold or bowl. Then put the cleaned grapes on top. Then fill the rest of the quark mass into the mold. Decorate with crumbled amarettini or brittle if you like.