Bring a large pot of salted water to a rolling boil. Add the fettuccine and cook according to package directions until al dente. Drain and set aside, drizzling and tossing with a little olive oil to prevent sticking while it sits. Add the avocado, garlic cloves, basil, hemp seeds, salt, lemon zest and juice, ground black pepper, and parmesan cheese (if desired) to a food processor or blender. Pulse to combine, then blend steadily until smooth. Portion the pasta into bowl, top with avocado pesto sauce and stir to combine. Drizzle with high quality extra virgin olive oil, sprinkle with flaky maldon sea salt and ground black pepper, and top with extra parmesan cheese, if desired. Enjoy right away! If you have leftovers, drizzle the top of the pesto with extra lemon juice and olive oil to create a protective coating to slow browning/oxidation of the avocado.