Wash and clean the rhubarb and cut into pieces approx. 2 cm in size. Cover with 50 ml of syrup and 1 tablespoon of water and simmer for about 10 minutes over medium heat and then leave to cool.
Mix the starch with 100 ml syrup and 200 ml water. Bring to a boil over medium heat, stirring constantly. As soon as the mixture has set, take the saucepan off the stove, let it cool down and put it in the fridge for about 1 hour. Then mix in the yogurt.
Pour the rhubarb compote into glasses and spread the cream on top.