Put the bananas with the water, vanilla sugar and citric acid in a blender and puree well.
Now cook the finished, mushy mass with the preserving sugar according to the instructions on the packet. Just before the end of the cooking process, add cocoa powder, noisette syrup and rum and stir well. Finally stir in chocolate droplets briefly, then fill immediately.
If you have children or want to avoid alcohol, simply choose a few drops of rum aroma instead of rum.
The amount given here is sufficient for 3 preserving jars of 212 ml each.