Boil salted water in a large pot. Add pasta and cook until al dente (8-10 minutes). Reserve 1/2 cup of pasta water, then drain.

In a blender, combine avocados, garlic, lemon juice, olive oil, salt, and pepper. Blend until smooth.

Toss the hot pasta with the avocado sauce in a large bowl. If too thick, add reserved pasta water to achieve desired consistency.

Garnish with Parmesan cheese if desired and serve immediately for optimal creaminess.