Heat the crème caramel until it reaches boiling point and pour into the dishes.
Leave to set in the refrigerator.
Caramelise the sugar in a pan and add 500 ml mandarin juice.
Reduce until you have a caramel sauce.
Boil 200 ml mandarin juice with the sugar and agar agar for a few minutes.
Allow to cool, then mix until you have a smooth gel and transfer to a piping bag.
Garnish with a segment of mandarin and the mandarin caramel sauce.