Boil the pasta: Bring a large pot of well-salted water to a boil. Cook pasta until just shy of al dente, according to package directions. Reserve at least 1 cup of the pasta water before draining.

Make the ricotta sauce base: In a large bowl, whisk together ricotta, Parmesan, lemon zest, lemon juice, garlic, olive oil, salt, and pepper. The mixture will be thick—that’s okay.

Loosen with pasta water: Add 1/4 cup hot pasta water to the ricotta mixture and whisk until creamy and smooth. Add more water a splash at a time if needed. You want a silky, pourable sauce.

Add the pasta: Toss the hot, drained pasta directly into the bowl with the sauce. The heat from the pasta will warm the ricotta gently and help it coat every strand.

Fold in veggies (optional): If using spinach, peas, or asparagus, add them now. The residual heat will wilt tender greens and warm vegetables through. Add more pasta water if the sauce tightens.

Taste and adjust: Add another squeeze of lemon for brightness, a pinch of salt, or a crack of pepper as needed. Finish with extra Parmesan.

Serve: Plate immediately. Garnish with chopped herbs, a pinch of red pepper flakes, and a little extra lemon zest if you like.