Wash the rhubarb and cut into large pieces. Preheat the oven to 175 °.
For the shortcrust pastry, knead all the ingredients together thoroughly and quickly. Let rest in the fridge for 15 minutes, then roll out in a buttered springform pan, don`t forget the edge!
Spread the rhubarb generously on top (I add a lot of vanilla sugar to it, otherwise it`s too sour for me, but it`s a matter of taste), can be in two layers, the rhubarb will collapse later.
Pre-bake for 20 minutes at 175 °.
Beat 2 egg yolks with 80g sugar and add the flour.
Beat the cream until stiff, beat the egg white until stiff. Fold both into the egg, sugar and flour mixture. (please do not stir anymore, just fold in).
Put the mixture on the cake and bake for about 45 minutes at the same heat.