In a double boiler over medium heat, combine high-quality white chocolate, butter, and heavy cream. Stir frequently until everything is completely melted and smooth, about 5-7 minutes.

In a mixing bowl, stir in the chopped cranberries and finely chopped pistachios into the melted chocolate mixture. Mix thoroughly until everything is evenly coated.

Transfer the combined mixture into a shallow container or bowl, spreading it out evenly. Cover and refrigerate for at least 2 hours, or until firm.

Once firm, roll small portions into smooth balls and place them on a parchment-lined baking sheet.

Roll each truffle in powdered sugar until fully coated.

Enjoy immediately or store in an airtight container.