Wash and clean the rhubarb and cut into pieces approx. 2 cm long. Core the dates and chop them into small cubes. Long slit the vanilla pod and scrape out the pulp.
Put all the ingredients in a saucepan that is not too small. Add a shot (approx. 50 ml) of water. Bring the mixture to a boil and let it simmer for about 5 minutes.
Fish the vanilla pod and star anise out of the pot. Finely puree the mixture, briefly bring to the boil again and pour into jars that have been rinsed with hot water. Turn glasses upside down for about 10 minutes. Makes approx. 450 g.