Combine all the dry ingredients in a blender or food processor.
Blend until everything is almost chopped, then slowly drizzle in the olive oil.
Pulse until combined. You can continue blending to make a silky, creamy pistachio pesto. Or make a more textured pesto that looks like a coarse paste.Taste and add salt to taste.
Transfer to a bowl or an air-tight container. Drizzle some olive oil on top. Serve and enjoy!
Notes
For the best flavor and texture, please use freshly grated parmesan cheese!
I did not add the salt with the dry ingredients in step 1 because the Parmesan already has some.
Pesto with pistachio has so few ingredients that I recommend using the best quality you can get your hands on.
If you want a textured pesto, please use a mortar pestle instead of a food processor or blender.