Preheat the oven to 350 degrees F.
Toast the pistachios for about 10 minutes until slightly brown. Remove from the oven and chop them.
Place the cranberries in a food processor and pulse until cranberries are chopped into small pieces. I use a mini-food processor and pulse about 10-15 times. Chopping them in the food processor helps ensure better distribution throughout the dough. You can also chop them by hand.
Place the butter, sugar and salt in the bowl of a stand mixer with the paddle attachment and mix on medium speed until the mixture is smooth, about 2 minutes. Stop the mixer, scrape down the bowl and add all the flour at once. Turn the mixer to low speed and mix until all the flour is just combined. The dough will be crumbly at this point. Increase the mixer speed to medium and mix until the dough has completely come together. Add the pistachios and the cranberries and mix on low speed until they are well combined into the dough.
Turn the cookie dough out onto a lightly floured surface. You can turn it out onto a large piece of parchment paper or Silpat. Use your hands to shape the dough into a rectangle and lightly flour the top of the dough. Do not use too much flour, just enough to keep the rolling pin from sticking.
Roll the dough out to 1/2-inch thick. Use a 2-inch round cookie cutter to cut out the cookies. Place the cookies on parchment lined cookie sheet about 1-inch apart. Prick each cookie in the center with a fork. Pricking the cookies will ensure they bake in the center.
Chill the dough in the refrigerator for at least 20 minutes. Chilling the dough will help the cookies hold their shape when baking.
Preheat the oven to 300 degrees F.
Bake the cookies for 25-30 minutes. The cookies will be a pale golden color. They’re not supposed to turn golden brown. The bottoms of the cookies will be slightly brown.NOTE: I use a shiny cookie sheet. If you use a darker pan the bottoms will be a little darker and the bottom edges will be noticeably light brown.
Take the cookies out of the oven and allow them to cool for about 5 minutes on the cookie sheet before moving them to a cookie rack.
The cookies can be stored in a container for about 1 week.