Note: To thin out the sauce three teaspoons of the pasta cooking water are added. Before draining the pasta, ladle out ½ of a cup of water. This is very important!
· 1 pound hot cooked penne
· 2 cups packed fresh basil leaves
· 2 small or one large garlic clove, peeled
· ⅓ cup extra-virgin olive oil
· 3 tablespoons freshly grated imported Parmigiano-Reggiano cheese
· 2 tablespoons pine nuts
· 3 teaspoons pasta cooking water
· 1 teaspoon kosher salt or to taste
· Freshly ground pepper
Cook pasta until al dente. Drain in colander reserving ½ cup of cooking water; toss with one tablespoon of olive oil and set aside.
Combine basil, garlic and pine nuts in a food processor until finely chopped. With the food processor turned on, slowly add olive oil in a steady stream through the feeding tube until mixture is smooth. Add the cheese and process until the sauce forms a slightly gritty texture. Stir in 2-3 teaspoons of the pasta cooking water. Season generously with salt and pepper. Serve over hot pasta or steamed vegetables.
Pesto will keep in the refrigerator for 3 days. Place in a jar and pour a thin layer of olive oil over top to prevent oxidation; cover tightly. Stir in oil before serving.