Drain the mango and collect the juice. Cut 1 mango piece into thin slices, puree the rest of the mango. Stir curd cheese, mascarpone, 5 tablespoons mango juice, lemon juice and sugar until smooth.
Spread the quark and mascarpone cream on dessert plates. Pour the mango puree over it and pull it through the cream with a wooden skewer. Decorate with mango wedges and lemon balm.