Mix the butter with the sugar until frothy. Gradually add the eggs. Mix the vanilla sugar with the flour, baking powder and starch. Mix with the sugar and butter foam until smooth. Pour the batter into a buttered springform pan.
Wash and peel the rhubarb, cut into pieces approx. 4 cm long and toss in plenty of sugar. Stick the pieces of rhubarb upright and tightly into the dough so that the dough swells up in the gaps. Bake at 160 degrees for 45-60 minutes. Serve dusted with powdered sugar!
Very tasty, not too sweet and doesn`t need any cream because it`s so juicy!