Dissolve the corn starch in a large pan with approx. 1dl of the apple juice. Add the remaining apple juice and the egg and sugar mixture and bring to the boil briefly, stirring constantly. Then let it cool completely (this can be prepared up to two days in advance).
Before serving, whip the cream until stiff and carefully fold it into the cold cream.
Decorate with dried (or fresh) apple rings and serve.
If you like, you can pour a shot of thurgados (or calvados) over it.