Place pine nuts in a small skillet over medium-low heat. Stir often, cooking for just a few minutes, until they start to brown. Remove from heat and cool.

Place basil, pine nuts, garlic, and parmesan in a the bowl of a food processor or blender. Pulse until a paste forms. Add 1/2 teaspoon salt and pulse to combine.

While running the machine, pour in olive oil, starting with 1/2 cup. Once the pesto emulsifies it will become a thick sauce. If you want thinner pest, add another 1/4 cup olive oil.