Bring a large pot of generously salted water to a rolling boil over high heat. Add 400g (14 oz) of spaghetti or linguine to the boiling water. Cook according to package directions until al dente, typically 8-10 minutes. Before draining, reserve at least 120ml (0.5 cup) of the starchy pasta water. Drain the pasta and set aside.

While the pasta is cooking, prepare the pistachio pesto. In a food processor, combine 150g (1.5 cups) of shelled, raw pistachios, 60g (2 cups, packed) of fresh basil leaves, 2 peeled garlic cloves, and 50g (0.5 cup, grated) of Parmesan cheese. Pulse a few times until the ingredients are coarsely chopped.

With the food processor running on low speed, slowly drizzle in 120ml (0.5 cup) of extra virgin olive oil. Continue processing until the mixture is mostly smooth but still has a slight texture. Scrape down the sides of the bowl as needed to ensure all ingredients are incorporated.

Add 1 tbsp (15ml) of fresh lemon juice to the pesto mixture. Season with salt and freshly ground black pepper to taste. Remember that the Parmesan cheese is already salty, so taste before adding too much salt.

Transfer the pesto from the food processor to a large bowl or back into the pot you used for the pasta (after draining). Add 120ml (0.5 cup) of heavy cream to the pesto and stir well to combine. This will create the creamy base for the sauce.

Add the drained, cooked pasta directly into the bowl or pot with the pistachio pesto sauce. Toss gently to coat the pasta evenly with the creamy pesto. If the sauce seems too thick, gradually add some of the reserved pasta water, a little at a time, until the desired creamy consistency is reached. The starch in the pasta water will help the sauce emulsify and cling to the pasta.

Serve the Creamy Pistachio Pesto Pasta immediately. Garnish each serving with a sprinkle of roughly chopped pistachios and an extra grating of Parmesan cheese, if desired. A final drizzle of extra virgin olive oil can also enhance the dish.