Bring a large pot of salted water to boil for pasta.

In a food processor, add basil, parsley, pistachios, garlic and salt. Turn on processor and add 1 1/2 cups of the olive oil in a slow, steady stream. Process to make a smooth paste, stopping to scrape down the sides of the bowl occasionally.

Add spaghetti to the boiling water and cook until al dente. Scrape half of the pesto into a large skillet over low heat and add 1 cup pasta water. Use a spider to drain pasta and transfer to the skillet. Drizzle with remaining 2 tablespoons olive oil and toss to coat the pasta with the pesto. Off heat, toss with the grated cheese.

NOTE: This recipe makes twice the amount of pesto you will need for 1 pound of pasta. You can freeze half of the pesto for future use, just pack in a plastic container with a thin film of olive oil. Thaw in refrigerator before using. You can also cut the recipe in half if you just want enough for 1 pound of pasta.