Whip egg whites separately from yolks, then fold in, stir in powdered sugar, and whip until foams. Stir in warm milk, keep whipping for a minute, and then add vanilla sugar and sieved flour. Stir quickly until of a good spreading consistency.

Place the dough into a greased and dust rectangular mold. Bake in the preheated to 420 °F (220 °C) oven for 10 minutes. Cool and unmold. Smear with confiture, roll up, and fold up in paper.

When serving, cut into portion size pieces.