Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.
In a mixing bowl, cream the softened butter and granulated sugar together until light and fluffy. This should take about 2-3 minutes using an electric mixer.
Add the vanilla extract and mix until combined.
Gradually add the all-purpose flour and salt to the butter mixture, mixing until just combined.
Gently fold in the chopped cranberries and pistachios using a spatula.
Turn the dough onto a lightly floured surface and shape it into a log. Wrap it in plastic wrap and refrigerate for about 30 minutes until firm.
Once chilled, remove the dough from the refrigerator. Slice the log into ¼-inch thick rounds and place them on the prepared baking sheet, spacing them about 1 inch apart.
Bake in the preheated oven for 20-25 minutes, or until the edges are lightly golden.
Remove from the oven and let the cookies cool on the baking sheet for 5 minutes before transferring them to a cooling rack.
If desired, dust the cooled cookies with powdered sugar before serving.