Mix the starch and 3 tablespoons of juice. Bring the rest of the juice and sugar to the boil. Stir in the starch, bring to the boil again and simmer for approx. 3 minutes. Fold in the cherries. Allow to cool slightly. Fill into 4 dessert bowls and leave to cool for at least 2 hours.
Mix the quark and milk until smooth. Season to taste with V-sugar and lemon juice. Spread on the cherries. Halve the puffed rice pieces diagonally and arrange on top.