A simple yet tasty 4-ingredient recipe from Gourmet Magazine, May 2004. I like to have this in my mix of holiday cookies because it's so low-maintenance. Prep time includes chill time. Also good dipped in chocolate rather than sugar.
Put oven rack in middle position and preheat oven to 350°F.
Toast hazelnuts in a shallow baking pan until fragrant and skins begin to loosen, about 6 minutes. Rub nuts in a kitchen towel to remove any loose skins (some skins may not come off) and cool to room temperature.
Pulse nuts and 1/4 cup sugar in a food processor until nuts are finely ground, then add flour and a pinch of salt, pulsing until combined. Add butter and pulse until dough just forms a ball. Divide dough in half, then roll dough on a work surface lightly dusted with sugar and flour into 2 (11-inch-long) logs (each about 1 inch wide). Chill, wrapped in plastic wrap, 1 hour.
Cut logs crosswise into 1/2-inch slices and arrange rounds 2 inches apart on 2 baking sheets.
Bake, 1 sheet at a time, until bottom edges just begin to turn pale golden, 12 to 15 minutes. Cool cookies on sheet 2 minutes. Place remaining 3 tablespoons sugar in a small dish and dip tops of cookies in it, then cool sugared cookies on a rack.
Cooks' notes: Dough can be chilled up to 12 hours or frozen, wrapped well in plastic wrap, up to 1 month. (Thaw before cutting and baking.) Cookies keep in an airtight container at room temperature 2 weeks.