While the water comes to a boil, make the sauce: In the base of a food processor, add the California Avocados, cheese, lemon juice and zest, onion powder, pepper, and garlic powder. Purée the mixture until smooth and season lightly with salt. Transfer the sauce to a large bowl.
Once the water comes to a boil, salt the water and add the fettuccine. Cook the pasta to a desired doneness, 7 to 10 minutes. Drain the pasta, reserving 2 cups of the cooking liquid. Add the cooked pasta to the large bowl and toss the pasta in with the dressing. The mixture will be thick. Use the cooking liquid to get the sauce to a creamy consistency. Toss in 4 tablespoons of pine nuts and 2 tablespoons of the chopped parsley, and season with any additional salt. Plate the pasta onto serving dishes and garnish with the remaining 2 tablespoons of pine nuts, tablespoon of chopped parsley and whole parsley leaves, then serve.