For the compote, wash, stone and quarter the plums. Bring juice and cinnamon to the boil in a pot. Add the plums and simmer for about 10 minutes. Stir starch with 2 tbsp. water until smooth. Stir into the compote and simmer while stirring for about 1 minute. Stir in rum. Let the compote cool down.
Whip the sour cream and cream until stiff, adding sugar and vanilla sugar. Pour cream into a piping bag with a large star-shaped spout.
Divide the compote between four dessert plates. Spray cream on top. Coarsely crumble the pork tubes and sprinkle with rock candy over the dessert.