Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.

In a dry skillet over medium heat, toast walnuts for about 5 minutes, stirring frequently, until they are fragrant and golden brown; let them cool before chopping.

In a mixing bowl, cream together the butter, confectioners' sugar, and vanilla extract until smooth and light.

Gradually mix in the flour and salt until a cohesive dough forms. Gently fold in the chopped walnuts.

Roll the dough into 1-inch balls and arrange them 1 inch apart on the baking sheet.

Bake for 12-15 minutes, or until the bottoms are lightly golden.

Roll the warm cookies in confectioners' sugar after baking and allow to cool on a rack. Roll again in sugar once completely cool.