Preheat the oven to 350°F (175°C) and line a baking sheet with parchment paper.
In a large mixing bowl, beat the softened butter until smooth and creamy.
Add the powdered sugar and continue mixing until light and fluffy.
Add the flour and mix gently until a soft dough begins to form.
Fold in the chopped pistachios and dried cranberries until evenly distributed throughout the dough.
Gather the dough together and shape it into a log. Wrap tightly and chill until firm.
Slice the chilled dough into even rounds about ¼-inch thick.
Arrange the cookie slices on the prepared baking sheet, leaving a little space between each one.
Bake for 10–12 minutes, or until the edges are just lightly golden.
Let the cookies cool on the baking sheet for 5 minutes, then transfer them to a wire rack to cool completely before serving.