In a large bowl, beat together the butter, brown sugar, and white sugar for 2-3 minutes. Add the vanilla extract and egg and beat until fluffy and light in color. Add the flour and baking soda and beat until flour is fully incorporated. Lastly, fold in the cranberries and pistachios.
Roll the cookie dough in wax paper into 2 logs about 1 ½ inches in diameter. Place both rolls on a baking sheet and place them in the freezer for 1 hour to firm up.
Preheat the oven to 350℉ about 10 minutes before you take the cookie dough out of the freezer. Line 2 baking sheets with parchment paper. Remove the cookie dough from the freezer and slice into ¼-inch cookies. Place 12 cookies on each pan and bake for 12-14 minutes or until bottoms are light golden brown.
Let the cookies cool on the baking sheet for 3 minutes and then transfer to a wire rack to finish cooling. Enjoy!