Place Hazelnut in a food processor and pulse until finely ground.
Add flour, butter and sugar and pulse until a ball of dough is formed.
Roll the dough between 2 sheets of parchment paper to 1/4" thick and place in the refrigerator for about 1 hour. (or overnight)
Preheat oven to 350F and line a baking pan with parchment paper.
Remove dough from the refrigerator use a cookie-cutter to cut cookies.
Cut half of the circles with 1/2" circles in the center.
Bake for 10-12 minutes on the middle rack. The cookies are ready when the sides are golden and are puffed in the center.
Remove from the oven and allow to cool completely.
Spread 1 tsp of Hazelnut spread on half the cookies, dust the rest of the cookies with confectionary sugar and place on top to create a sandwich cookie.