Begin by preheating your oven to 350°F (175°C). Prepare a baking sheet by lining it with parchment paper to prevent sticking.
In a large mixing bowl, use an electric mixer to cream the softened butter and sifted powdered sugar together. Mix on medium speed until the mixture is light, fluffy, and well combined, about 2-3 minutes.
Add in the vanilla extract and the optional orange zest, mixing briefly until incorporated into the buttery mixture.
Gradually sift in the all-purpose flour and sprinkle the salt, mixing slowly until a soft dough begins to form. It's important not to overmix—stop as soon as the dough comes together.
Gently fold in the chopped dried cranberries and pistachios, ensuring they are evenly distributed throughout the dough for a balanced flavor in every bite.
Transfer the dough onto a clean, lightly floured surface and shape it into a log, about 2 inches in diameter. Wrap the log tightly in plastic wrap and refrigerate for a minimum of 30 minutes.
After chilling, take the log out of the refrigerator and with a sharp knife, slice it into rounds approximately 1/4 inch thick. Arrange the slices on the prepared baking sheet, leaving a couple of inches of space between each cookie to allow for spreading.
Place the baking sheet in the preheated oven and bake for 12-15 minutes, or until the edges of the cookies turn a light golden brown.
Once baked, remove the cookies from the oven and let them rest on the baking sheet for about 5 minutes before transferring to a wire rack to cool completely.
Notes
For an elegant touch, dust the cooled cookies with powdered sugar and garnish with whole pistachios and cranberries.