Lightly toast pine nuts until golden in a dry skillet or pan over medium heat. Remove from pan and allow to cool.
In a food processor or blender, combine the basil leaves, pine nuts, garlic, olive oil and parmesan cheese and process for a couple of minutes until a paste forms. Do not over-process into a puree, as we want to retain some texture. Season to taste. Depending on the use you're giving it, you may need to thin it out with a tablespoon or so of water.
If paleo or dairy free, substitute the Parmesan cheese with nutritional yeast. Add it little by little to taste.