Boil up the milk. Cook rice pudding in it at low heat for about 45 minutes. Finely chop the marzipan and stir in. Season to taste with sweetened condensed milk. Meanwhile clean, wash, halve and stone the plums for the compote.
Stir red fruit jelly powder, 4 tablespoons of juice and sugar until smooth. Boil up the rest of the juice, 250 ml water, plums and lemon peel. Stir in the mixed powder. Boil up briefly while stirring. Cut rice pudding into balls with an ice-cream scoop.
Serve with the plum compote. Serve decorated with flaked almonds, lemon and fine mint stems.