Set Oven to 350 °F.
Mix Dry Ingredients including lemon peel (zest) in mixing bowl.
Dump dry ingredients onto a clean countertop.
Push dry ingredients together to form a volcano-shaped pile with 'well' on top. Pour egg yolks into 'well'.
Work egg yolks into dry ingredients with hands.
Add softened butter a little at a time and continue to work the dough with hands until a dough ball is formed. **If the dough is too dry add 1 whole egg**.
Wrap the dough ball in plastic wrap and put it in the refrigerator to chill for about 1/2 hour **dough can also be left in the fridge overnight **
Remove chilled dough from the refrigerator if the dough was left overnight allow it to sit at room temperature for about a half-hour to soften it slightly.
Line cookie sheets with parchment paper.
Lightly flour the clean countertop.
Cut dough ball in half. Setting one half of dough aside to use later.
Pinch a small amount of dough from the ball and roll on the floured countertop to form a small marble-sized ball. Work the dough to form a crescent moon-shaped cookie.
Place on lined cookie sheet. **One cookie sheets holds between 35-45 cookies depending upon the size of each cookie**
Place cookie sheet on the middle rack of the oven and bake until edges of cookies turn a light brown colour (approximately 12 minutes). If cookies are not brown add another 2 - 3 minutes of baking time.
In a shallow pan add 1 cup of powdered sugar and 3 packs of vanilla sugar.
Remove cookies from the oven.
While cookies are still warm add a few cookies at a time to the sugar in the shallow pan turning to coat.
Place coated cookies on your favorite Christmas platter and enjoy!!