For the dough, beat the egg whites until stiff. It must be so firm that a knife cut remains visible. Underneath, by the tablespoonful, whip the sifted powdered sugar with the vanilla sugar. Then stir in the juice of one lemon, lemon zest, baking oil and a good half of the almond kernels. knead in the rest of the almond kernels until the dough hardly sticks. On a baking board (table top) sprinkled thickly with almond kernels, roll out the dough to a good 1/2 cm thickness. Cut out crescents and place them on a baking sheet covered with well-greased parchment paper.
Bake at 130-150 degrees in a heated oven for 30-45 minutes.
For the icing, mix the sifted powdered sugar with enough juice of one lemon to make a thick mixture. Brush the cooled cookies with it.