Preheat oven to 350ºF (180ºC).
Combine ¾ of the parmesan cheese with the flour and the butter and form a dough.
Roll dough on a horizontal surface to form a ½ inch (1 cm) thick rectangle.
Cut dough in strips 3 x ½ inches (6 x 1 cm). Brush egg yolk on top and sprinkle with the remaining parmesan cheese. Bake for 20 minutes or until golden.
Preparation Time: 35 minutes