Soak the gelatin in enough cold water.
Stir through the juice of one lemon, sugar and cream quark. Next, stir in the heavy cream.
Put the tangerine juice in a small pan and heat just slightly. Remove from heat, squeeze the soaked gelatin and let it melt in the juice. Whisk in a few spoonfuls of cream, then stir this mixture into the remaining cream. Fill the cream into glasses or dessert bowls and leave to cool for at least 120 minutes.
To serve, garnish the cream with mandarin orange slices.
Tip: The cream keeps fresh in the refrigerator up to 3-4 days.