Separate the eggs. Mix the egg yolks with the powdered sugar and vanilla sugar until frothy, beat the egg whites until stiff. Together with the sifted flour mixed with cornstarch, fold loosely into the egg yolk and sugar mixture.
Line a loaf pan with parchment paper. Place the oven in the oven at 180 degrees, fill the mold with the dough and bake for around 30-40 minutes.
Tip: You need this biscuit as a basis for many Italian desserts.