Pesto has now become a household sauce: it is easy to make, and its freshness of flavor has made it an often found friend on American tables. Pesto is at its best when used immediately after it is made, though it can be refrigerated for up to a few weeks if it’s spooned into a container, topped with olive oil, and sealed tight. If you find yourself with an abundance of basil in summer, make some pesto and store it in small portions in the freezer, where it will last for up to a few months. (Frozen pesto gives a great burst of fresh flavor to hearty winter soups and pasta sauces.) I’ve given you two methods for how to make this, with a mortar and pestle or with a food processor, but the results either way are delicious.
4 cups loosely packed fresh basil leaves (about 60 small or 30 large fresh basil leaves), gently washed and dried
Pinch of coarse sea salt
2 cloves garlic, peeled
3 tablespoons pine nuts, lightly toasted
2 tablespoons freshly and finely grated Pecorino Romano cheese
2 tablespoons freshly and finely grated Grana Padano or Parmigiano-Reggiano cheese
3 to 4 tablespoons extra-virgin olive oil
To make the pesto in a mortar: Place a few leaves of the basil in the bottom of a mortar, and sprinkle the salt over them. Crush the leaves coarsely with the pestle, add a few more leaves, and continue crushing, adding new leaves each time those in the mortar are crushed, until all the leaves are coarsely ground. Toss in the garlic, and pound until the mixture forms a smooth paste. Add the pine nuts, and grind them to a paste. Stir in the cheeses, then enough of the olive oil to give the pesto a creamy consistency.
To make the pesto in a food processor: Combine the basil, salt, and garlic in the food processor, add 2 tablespoons of the oil, and blend at low speed, stopping frequently to press the basil down around the blades, until a coarse paste forms. Toss in the pine nuts, and pour in the remaining olive oil. Blend until the pine nuts are finely ground. Stir in the grated cheeses to form a creamy paste.