Toast the pine nuts in a saute pan over medium high heat, tossing frequently (or mixing) until they are golden brown. Remove from the heat and transfer to a bowl to ensure they don't continue cooking in the warm pan.
Place the basil and garlic in the bowl of a food processor fitted with a steel blade. Pulse a few times to coarsely chop. Scrape down the sides.
Add the pine nuts to the oil in a measuring cup. With the motor running, slowly pour the oil and nuts through the tube. Stop processing as soon as all of the oil and nuts have been added.
Scrape the sides down and pulse once or twice to make sure there are no large chunks. The mixture should have some texture and not be too smooth.
Fold in the cheese and store in the refrigerator. It will keep for up to 2 weeks.
Pesto freezes well, but do not add the cheese if you plan to freeze.