How to Make It
Preheat oven to 400°F. Beat butter with a heavy-duty stand mixer on medium speed until creamy. Add sugar and vanilla, and beat until well incorporated. Add flour; beat until blended. Stir in walnuts.
Shape into 16 (1-inch) balls, and roll each ball into a 3-inch rope. Place ropes 2 inches apart on parchment paper-lined baking sheets, and curve into crescents.
Bake in preheated oven until golden brown, 9 to 10 minutes, switching pans top rack to bottom rack halfway through baking. Cool on pans 1 minute. Roll warm cookies in powdered sugar, and cool completely, about 30 minutes. Dust with additional powdered sugar, if desired.