Preheat the oven to 400 degrees F.
Measure out two cups of all purpose flour and place in a large bowl. Set aside.
Chop the nuts using a large knife. Walnuts are quite easy to chop but avoid cutting them into very tiny pieces (they easily turn into powder) or into pieces that are so large the dough will crumble. Place in a small bowl and set aside.
Cut the butter into roughly tablespoon size pieces and add to the bowl of a stand mixer fitted with a paddle attachment. The butter pieces don't have to be perfect.
Add the powdered sugar to butter and mix on low speed until creamed together, about 1 to 2 minutes.
Add the vanilla extract and mix to combine.
Pour the flour into the butter and sugar mixture and mix on low until combined. Be sure to scrape down the sides of the bowl and up from the bottom so there are no streaks of flour.
Add the chopped walnuts and mix briefly until they are combined. You can also use a wooden spoon and stir them in by hand.
Line your baking sheets with parchment paper or silicone mats.
Scoop out the dough using a cookie scoop or a tablespoon.
Roll the dough between your hands to make a ball and place each cookie on the prepared sheets. They do not spread too much, so you can leave about an inch between cookies.
Bake for 12 minutes until the bottoms are just golden. If you are using two trays, rotate them midway through the bake time.
Remove the hot cookies to a wire rack.
Place the remaining 1 1/2 cups of powdered sugar in a shallow bowl.
As soon as the cookies are cool enough to handle - but while they are still quite warm - roll them in the powdered sugar.
Return the coated cookies to the wire rack to finish cooling, then roll them in powdered sugar one more time.