Preheat the oven to 175 - 200 ° C fan-assisted air.
Beat the softened butter with sugar and vanilla sugar until frothy. Add eggs, salt and water. Mix the flour with the cornstarch and baking powder, sieve into the mixture and stir everything together. Finally fold in the chocolate chips.
Put the dough on the baking sheet with the help of a teaspoon. Bake the cookies for 15 minutes.