Squeeze six oranges and measure 1/2 litre of juice. Soak gelatine in cold water for about 10 minutes. Pour orange juice through a sieve. Add vanillin sugar and sugar and warm up slightly.
Squeeze gelatine vigorously and dissolve in a small pot. Mix with the fruit juice. Pour into 4 glasses and chill until the juice gels. In the meantime peel the remaining oranges generously so that the white skin is completely removed.
Cut out the flesh between the parting skins, sprinkle with orange liqueur and leave to stand briefly. For the sauce, place the cold milk and vanilla sauce powder in a bowl and whisk vigorously for 1 minute.
Season with cinnamon. Before serving, place the orange filets on the jelly. Pour sauce over them. Garnish with mint leaves.