Preheat the oven to 350°F (175°C). Line a large baking sheet with parchment paper.
Finely chop the cashews with a sharp knife or pulse them briefly in a food processor. Do not process them into a paste.
Add the softened butter, sifted powdered sugar, and salt to a large mixing bowl. Beat with an electric mixer for 3 to 4 minutes, until pale, smooth, and fluffy.
Add the vanilla extract and mix until combined.
Gradually add the all-purpose flour. Mix on low speed just until a soft, even dough forms. Do not overmix.
Add the chopped cashews and gently fold them into the dough until evenly distributed.
Use a small cookie scoop to portion the dough onto the prepared baking sheet, leaving a little space between each cookie.
Bake for approximately 15 minutes, until the cookies are set and lightly golden around the bottom edges. The tops should remain fairly pale.
Remove the baking sheet from the oven and allow the cookies to cool on the pan for 10 minutes.
Place the powdered sugar for coating in a shallow bowl or deep plate. Carefully coat each warm cookie on both sides, then transfer it to a wire cooling rack.
Allow the cookies to cool completely. Roll them in powdered sugar a second time before serving.
