How to make
Whip the butter and powdered sugar for 10 minutes and successively add the yolks (2), the milk in which you have dissolved the ammonium bicarbonate and flour. Spread the resulting dough in a tray with a diameter of 11 3/4″ (30 cm) and bake in a moderate oven until light golden in color.
Put the baked cake in a suitable plate and let it cool completely. Beat 2 egg whites with raspberry or sour cherry syrup. You can also add whole fruits, pitted.
Beat the mixture continuously until it becomes thick and significantly increases its volume, then smear it on the cake. Enjoy!