Cook your pasta according to the package directions.
While the pasta is cooking, add the oil, lemon juice, 3/4 of the lemon zest and minced garlic to a blender & lightly mix. Add the avocado and salt & blend until smooth.
Once you pasta is cooked, reserve a 1/2 cup of the water from cooking. Slowly add the pasta water to the avocado sauce to get your desired consistency.
Drain the pasta. Mix the pasta and sauce. Garnish with the remaining lemon zest and freshly ground black pepper. Serve immediately.