Add garlic, nuts, salt, and cheese. Process until pureed.
Taste the mixture at this point. You can add more salt if needed (even a touch more cheese). Add a little more olive oil if it seems to thick.
You can keep fresh pesto in a jar for 5 days in the refrigerator. Keep a thin layer of olive oil on the top of the pesto to keep from browning (if not covered, it may turn brown on top, but this in normal.) You can also freeze pesto for a couple of months. An option for freezing is to use an ice tray and make pesto cubes. Then you only use what you need without thawing entire amount.