Clean, wash and cut the rhubarb into small pieces. Boil up with 200 ml water and cinnamon stick. Simmer for 6-8 minutes until the rhubarb falls apart. Remove the cinnamon stick.
Stir the red berry jelly powder, sugar and 5-6 tablespoons of water until smooth. Stir into the rhubarb and simmer for about 1 minute. Pour the groats into a bowl, place the foil directly on the surface to avoid skin formation.
Let the groats cool down.
Coarsely crumble the Amarettini, sprinkle on the groats. Serve with liquid cream.