Cook the pasta

• Bring a pot of salted water to a boil and cook the pasta until al dente, following the package directions.
• Before draining, reserve some of the pasta water.

Make the ricotta sauce

• In a bowl, combine the ricotta, olive oil, lemon zest and lemon juice.
• Season with salt and pepper and stir until well combined.
• Taste and adjust the seasoning as needed.

Combine pasta and sauce

• Add the ricotta sauce to the drained pasta with part of the reserved pasta water.
• Stir well to coat the pasta evenly, adding more pasta water as needed until creamy.
• Fold in the spinach if using.

Serve

• Serve immediately, garnished with extra Parmesan, chilli flakes and lemon wedges if desired.