2teaspoonsvanilla sugar(or one tablespoon of vanilla extract)
1cupground nuts,see notes
For the Topping:
In a mixing bowl, use a hand-held mixer to beat together the butter, egg yolks, and vanilla sugar until just mixed. (If using vanilla extract instead of the vanilla sugar, add it now, but omit one egg yolk.)
Next, add in the flour, and ground nuts. Beat in on low speed. The mixture will be crumbly. Knead together and form into a log. Wrap in plastic wrap and refrigerate for 1 hour.
When ready to bake, preheat oven to 350°F. Prepare a baking sheet by lining it with parchment paper or a silicone baking mat. Set aside.
Pull about 1 tablespoon of cookie dough from the log. Roll in your hand and form into a crescent shape. Set it down on the prepared baking sheet, leaving 2 inches of space between each cookie.
Bake for 12 minutes.
Remove from oven and allow to cool for 2 minutes.
Transfer to a wire cooling rack and dust liberally with confectioner's sugar. Allow cookies to fully cool before storing.
Measure the one cup of nuts after being ground, not before.