Place the sugar, salt, vanilla sugar, lemon zest, flour and starch on the worktop, make a well in the center and add the egg white and the martini. Put butter in flakes on top and knead everything into a smooth dough. Shape into a ball and wrap in foil and put in the refrigerator for 30 minutes.
Line a baking sheet with parchment paper. Preheat the oven to 180 ° C. Roll out the dough and cut out. Bake in the oven for 6 - 8 minutes. Let cool down. Mix a glaze from powdered sugar and martini, glaze the cookies and garnish with lemon zest.
Depending on the size of the cookies, the amount is 4 - 5 trays.