Add all ingredients to a food processor. 

Process for 5 to 10 minutes on low. The amount of time will be determined by the power of your food processor and the consistency you want in your pistachio butter. 

The pistachios will go from a sandy texture to a playdough consistency before it starts to get smooth. If you've never done this before, for a few minutes it will seem like there's no way your pistachio spread will become smooth, but just keep running the food processor and it will eventually smooth out and become creamy. 

When you get the consistency you want, make sure to taste to see if you need to add more salt or honey.