In a large mixing bowl, beat the butter until light and smooth.

Add ½ cup powdered sugar and vanilla and beat well again.

Add flour and mix until blended; stir in nuts.

Shape the dough into a flattened ball.

Wrap tightly in plastic wrap and refrigerate until cold.

Line cookie sheets with parchment paper.

Shape dough into 1-inch balls and place on the prepared cookie sheets.

Bake at 325° for 20 minutes, or until golden brown and baked through.

While the first batch of cookies is baking, sift ¼ cup powdered sugar into a bowl.

When the cookies are removed from the oven and while still warm, roll them in the powdered sugar and cool on wire rack.