Peel the orange so that the white skin is completely removed. Remove the fillets with a sharp knife between the parting skins. Press the juice from the parting skins into a bowl.
Wash and halve the grapes. Apple wash, halve, remove seeds. Cut apple halves into small pieces. Peel and slice the banana. Mix fruit with orange liqueur and 1 teaspoon sugar.
Melt the chocolate over a warm water bath, let it cool down lukewarm. Pour fruit salad into 4 glasses. Whip cream until semi-stiff. Mix mascarpone, vanilla pulp and 1 tsp. sugar with the whisk of the hand mixer.
Fold in the cream. Fold the liquid chocolate into the mascarpone cream and immediately pour into the glasses on top of the fruit salad.