How to Make It
Preheat the oven to 350°. Spread the walnuts in a pie plate and bake for 6 minutes, or until golden. Let cool, then finely chop. Leave the oven on.
Using a handheld electric mixer, beat the butter with 1/2 cup of the sugar at medium speed until creamy. Beat in the flour, toasted walnuts, vanilla and salt at low speed.
Shape the dough into 1-inch balls and transfer them to a baking sheet. Bake for 15 to 20 minutes, or until firm, then let cool on the baking sheet for 5 minutes. Roll the warm cookies in the remaining 1 cup of sugar, then transfer to wax paper. Roll 2 or 3 more times in the sugar and let cool completely until set.