
In a small bowl mix together the yolks, butter and salt. Chill for 20-30 minutes.
Mix the zest, limoncello and vanilla, let sit 20-30 minutes.
In a the stand mixer whisk the flour and sugar add the chilled yolk mixture and zest mixture, combine on low (it will be crumbly), then increase to #2 speed and add the half and half one tablespoon at a time until almost combined.
Move the dough to a lightly floured flat surface and gently knead to form a compact soft dough. Wrap in plastic wrap and chill 60 minutes. Roll on a lightly floured flat surface to ¼ inch thick and cut out with medium cookie cutters, place them on parchment paper lined baking sheets.
While the oven is pre-heating to 350F/180C chill the cookies for 15-20 minutes. Bake for 12-15 minutes or until edges start to turn golden brown. remove from the oven and let cool 10 minutes on the pan then move to a wire rack to cool completely. Serve plain, dusted with powdered sugar or drizzled with a limoncello glaze. Enjoy!
Stir together the sifted powdered sugar, limoncell or limoncello cream or milk until smooth. Add more or less cream to reach desired thickness.