Drain the morello cherries well, collecting the juice.
Mix 125 g of mascarpone with the creme fraiche and 4 tablespoons of Nutella until creamy. Mix the remaining mascarpone with the quark, vanilla sugar, sugar and milk.
Mix the lemon juice with the juice from the morello cherries. Break the ladyfingers into pieces, dip them briefly in the juice and divide into four glasses.
Spread the Nutella mascarpone on top, cover with the morello cherries and cover with the light mascarpone cream. Serve the tiramisu with the rest of the Nutella cream and garnish with morello cherries and lemon balm, if desired.