Wrap in wax paper and refrigerate for at least 2 hours.
Remove from the fridge and slice into 1/4" rounds.
Place on greased cookie sheets and bake in a preheated oven @ 350 degrees for 10 - 12 minutes.
Notes
A food processor is a great tool for chopping nuts quickly.
When making these shortbread cookies, be sure to allow them to chill for at least two hours in the fridge. This allows for the dough to harden and the ingredients to set within the shortbread roll. If the cookies begin to crumble when you try to cut them, then you know that you need to allow the dough to set longer.
These pistachio shortbread cookies can be stored in an airtight container at room temperature for up to 5 days or in the freezer for 3 months.
Try different variations of this recipe. Instead of pistachios, use pecans, walnuts, or almonds. Substitute dark chocolate chips for the white and add orange zest. There are so many yummy combos to choose from.
It's also fun to dip the cooled cookies in melted white chocolate for a fun, festive look!