- ¾ cup walnut halves
- 1¼ cups confectioners’ sugar
- ¼ teaspoon salt
- ½ cup (1 stick) unsalted butter, cut into tablespoons
- ½ teaspoon vanilla extract
- 1 cup all-purpose flour
- Place walnuts, ¼ cup confectioners’ sugar, and salt in a food processor, pulse to break up nuts, then process until nuts are finely ground. Add butter a few pieces at a time, pulsing to incorporate, then process until mixture is smooth; pulse in vanilla. Add flour and pulse until incorporated. Process until dough begins to form a ball. Place dough on large piece of plastic wrap, form into a very flat disc, cover completely with wrap, and refrigerate until firm enough to roll into balls, at least 2 hours or overnight.
- Preheat oven to 350 degrees F. Line 2 rimmed cookie sheets with parchment paper.
- Roll dough between your lightly floured palms into 1-inch balls and place 2 inches apart on cookie sheets, Gently flatten just enough so they don’t; roll off.
- Bake until light golden brown around edges, about 15 minutes. Place pan on rack to cool for 5 minutes, then sift remaining 1 cup confectioners’ sugar over warm cookies. After cookies have cooled completely, roll them in sugar on the sheets to cover completely.