Peel and wash the rhubarb and cut into small pieces. Separate eggs. Mix the fat with sugar, vanilla sugar, a pinch of salt and the egg yolk until frothy. Mix in the ground almonds, flour and baking powder. Beat the egg whites until stiff. Carefully fold in the rhubarb and egg white. Put the dough in a wreath dish that has been greased and sprinkled with breadcrumbs and bake for about 1 hour.
Rush onto a wire rack to cool, if you want, you can sprinkle the wreath with powdered sugar before serving.
Since the rhubarb is processed raw in the batter, the cake stays fresh and extremely juicy for a long time.
This recipe is also suitable for currants, cherries, chopped apples and plums / plums!