Roast the pine (or walnuts) nuts, in a medium skillet over medium heat, stirring frequently until nice and fragrant, 3 to 5 minutes. Watch carefully to ensure the nuts don't burn! Place aside and let cool for a few minutes. Roasting the nuts is optional, however it increases the flavour of the nuts and will improve the taste of your finished pesto!
Place basil leaves, parmesan, salt and garlic into your food processor. Pulse the mixture until thoroughly blended.
With your processor running, slowly add the olive oil in a steady stream. Once blended add the nuts and process for about 20 seconds (longer if you want your nuts finer). You may have to pause during this process and scrape down the sides, if necessary.
Store pesto in the refrigerator for a couple weeks or in the freezer for a few months.