Boil the pasta in well-salted water until al dente. Reserve 1/2 cup pasta water, then drain.
Blend the silken tofu, spinach, garlic, nutritional yeast, olive oil, lemon juice, salt, and pepper until completely smooth.
Thin the sauce with reserved pasta water as needed to reach a pourable consistency.
Warm the sauce gently in a skillet over low heat for 2 to 3 minutes, if desired.
Add the drained pasta to the sauce and toss until fully coated.
Serve topped with fresh basil and vegan parmesan or extra nutritional yeast.