Bring a large pot of salted water to a boil.
Meanwhile, zest and juice the lemon into a high-powered blender or food processor.
Add the cottage cheese, Parmesan, oil, garlic, spinach and basil. (Add wallnuts too) Blend until very smooth. (in a food processor, this can take up to five minutes.) Add pepper and salt too taste.
Add the pasta to the boiling water and cook until al dente according to package directions.
Scoop out 1 ½ cups of the pasta water, then drain the pasta and return to the pot.
With the blender running, pour ¾ cup of the pasta water into the cottage cheese mixture and blend until smooth.
Off the heat, add the cottage cheese mixture to the pasta.
Toss vigorously until the pasta is coated in sauce, adding more pasta water as needed until glossy.
Season to taste with salt.
Serve topped with a drizzle of olive oil and more Parmesan.
