Wash and peel the rhubarb, cut into 1.5 to 2 cm thick slices and sprinkle with 1 teaspoon of cinnamon.
Mix the butter with sugar, vanilla sugar, eggs and cream. Mix the baking powder and flour and stir into the batter. Put the dough in a springform pan and top with the rhubarb.
Bake the cake in a preheated oven at 200 ° C (gas mark 3) for 30-35 minutes. Mix 2 teaspoons of cinnamon and 3 tablespoons of sugar and sprinkle over the warm cake.