Separate eggs. First whip the egg whites, then the cream until stiff. Mix the quark with the egg yolks, sugar, lemon juice and zest. Fold in the whipped cream and whipped cream. Drain the sour cherries. Chop nuts. Roughly crumble the ladyfingers and cookies. Put the quark cream, sour cherries, nuts and breadcrumbs in layers in a bowl and sprinkle with the grated chocolate. Cover and leave to stand in the refrigerator for at least 5 hours.