Bring a large pot of salted water to a rolling boil over high heat. Add pasta and cook according to package instructions until al dente, about 8-10 minutes. Reserve a cup of pasta water before draining.

In a mixing bowl, combine ricotta, olive oil, Parmesan cheese, and the zest and juice of the lemon. Mix until smooth, then season with salt and pepper to taste.

In the last minute of cooking the pasta, add fresh baby spinach directly into the pot and stir until wilted.

Drain pasta and spinach, return to pot, and stir in ricotta sauce and a splash of reserved pasta water until well combined.

Serve immediately, garnished with extra Parmesan, a drizzle of olive oil, lemon juice, and optional red pepper flakes.