Soak gelatine in cold water. Cut open the vanilla pod and scrape out the pulp with the back of a knife. Bring cream, milk, 3 tbsp. sugar, vanilla pulp and vanilla pod to the boil. Simmer over medium heat for 10-15 minutes.
Allow the cream to cool slightly, remove the vanilla pod. Squeeze the gelatine and dissolve in the hot cream while stirring. Leave to cool. Pour into 4-6 glasses and chill for at least 6 hours, preferably overnight.
Clean, wash and cut the rhubarb into pieces. Boil 1/8 l apple juice and 75 g sugar. Steam rhubarb for 3-5 minutes. Stir starch and 3 tbsp. apple juice until smooth. Bind rhubarb with it. Let the compote cool down.
Before serving, spread compote over the cream. Serve the rest separately.