Add the basil leaves, the garlic and the cheese to a food processor with the chopping blade. Chop for 15 seconds until all the ingredients are finely chopped.
Toast the pine nuts in a dry frying pan over medium heat. Shake the pan (like you are flipping an omelet) every few minutes or stir to ensure all sides get browned. You want to cook them until they are a nice golden brown.
While the pine nuts are still hot, add them to the food processor and chop for another 10 to 20 seconds.
While the food processor is running, slowly add the olive oil. Blend until fully mixed.