Mix the washed, pitted, chopped plums with the cinnamon, vanilla pulp, vanilla pod and sugar and leave to stand overnight, covered. The next day, remove the vanilla pod and bring the mixture to the boil while stirring and let it boil for 4 minutes according to the instructions on the package. If you like, you can chop up the jam a little with a hand blender. Now add the rum and stir well. Pour hot into well-cleaned Twist Off jars and close tightly.