Preheat your oven to 350°F (175°C). Beat together butter and powdered sugar until light and fluffy.

Sift flour into the butter mixture, then fold in chopped pistachios carefully.

Divide dough into logs, wrap in plastic, and refrigerate for at least 2 hours.

Slice chilled logs into ¼-inch rounds and place on a parchment-lined baking sheet.

Bake for 10-12 minutes until edges are lightly golden. Let cool for 5 minutes on the baking sheet.

Transfer to wire rack to cool completely.