Preheat the oven to 400°F and line 2 large cookie sheets with parchment paper or a silicone liner.

Add ½ cup of powdered sugar and beat on low for 1 minute, until the sugar is absorbed in the butter.

Add the vanilla extract, cinnamon, and salt and beat for a minute.

Now add the all-purpose flour and fold it in with a spatula.

Once all the flour is incorporated, add the finely chopped walnuts and fold them in.

Using a 1-tablespoon measuring spoon, form 1-inch balls from the cookie dough, and place them on the prepared cookie sheet. 

Bake at 400F for 10 minutes.

Let the cookies cool for 5 minutes and then immediately roll them in powdered sugar. The cookies should be warm. Most of the sugar from this coat will get absorbed into the cookies.

Once all the warm cookies are rolled in powdered sugar, let them cool completely.

Now roll each cooled cookie again in powdered sugar. 

Serve immediately or store in an air-tight container for up to a week.