For the vanilla crescents, mix the flour with the almonds, hazelnuts, sugar, salt together, then add the butter flakes wise and the egg yolk and knead everything into a dough.
Form the dough into a ball and wrap it either in aluminum foil or cling film and put it in the refrigerator for about 2 hours.
Then take the dough out of the fridge, form it into pencil-thick rolls and cut the rolls into 5 cm long pieces.
Form the pieces into croissants and bake at approx. 200 °C on the middle shelf for approx. 10 – 12 minutes. Mix the powdered sugar and vanilla sugar together and sift onto the croissants as soon as they are baked.