Soak gelatine in cold water. Heat the milk in a pot and dissolve the marzipan in it at low heat while stirring. Add liqueur and stir in. Remove the pot from the stove. Separate the egg and stir the egg yolk into the marzipan mixture.
Squeeze the gelatine well and dissolve it in the still warm marzipan mixture. Chill for about 1/2 hour. In the meantime whip cream until stiff. When the marzipan mixture begins to gel, add cream and fold in.
Beat the egg whites until stiff, carefully fold into the marzipan mousse and fill into a flat dish. Leave to set in the fridge for approx. 2 hours. In the meantime drain the cherries. Collect the juice and put it into a pot together with the sugar and the cinnamon sticks.
Mix cornstarch and 2 tablespoons of juice. Bring the juice to the boil. Remove the pot from the stove and thicken with the starch. Bring to the boil again. Fold in the cherries and let them cool down.
Cut off the mousse with a tablespoon and shape into cams with the help of a second tablespoon. Arrange on plates together with the cherry sauce and sprinkle with pistachios. Serve with lemon balm, a slice of orange and peel spirals decorated as desired.