Instructions

1. Measure the quantity of fresh basil at your disposal by stripping the leaves from their stems and packing them tightly into a measuring cup. A small food processor can accommodate roughly 3/4 cup to 1 cup of tightly packed basil, while a full-sized processor can handle 2 to 3 cups.

2. Chop a clove of garlic for every cup of basil leaves you're using. Sprinkle the garlic with salt, and transfer it to the bowl of your food processor.

3. Add half the basil and pulse a few times to chop it coarsely; then add the remainder. With the motor running, add olive oil in a thin stream until the garlic and basil come together to make a rough paste. You may need up to 1/4 of olive oil per cup of basil leaves.

4. Stop the machine and add 1 to 2 tablespoons of toasted pine nuts per cup of basil leaves. Start the machine again, and process the pesto until the nuts and basil form a smooth paste with an even texture.

5. Finish the sauce by stirring in up to 1/4 cup of Parmesan cheese per cup of basil leaves, either by hand with a spoon or by pulsing your food processor until it's incorporated. Some cooks add a tablespoon or two of softened butter at this stage as well, to make the sauce creamier, but that's optional.