2 cups basil leaves, chopped (feel free to substitute other herbs or leafy greens as well; ideas include mizuna, spinach, arugula, cilantro, and parsley)
2 garlic cloves, minced
1 tsp salt
¼ cup pine nuts (walnuts, almonds, and pecans are also delicious)
¼ cup Parmigiano Reggiano cheese
¾ cup olive oil or slightly more
Wash and dry the basil leaves and dry well.
Using a mortar and pestle, put in basil, pine nuts, garlic and a pinch of salt. Pound all the ingredients with the pestle using a circular motion to pull all of the ingredients to the center of the mortar. Pounding is done when the ingredients form into a paste with a slightly chunky texture.
Transfer from mortar to a bowl and add olive oil in a very, very slow stream, mixing all the while. Mix with cheese. Adjust oil if necessary.
If not using immediately, put in a jar and pour a thin layer of oil on top to keep that fresh green color.