In a large pot of boiling salted water, cook the pasta according to the package directions until it's al dente.
Meanwhile, prepare the ricotta sauce. In a medium bowl, combine ricotta, olive oil, Parmesan cheese, garlic, lemon zest, and juice. Season with 1/4 teaspoon of salt and a generous pinch of pepper. Stir until the ingredients are well combined. Taste to ensure the seasoning meets your preferences.
During the last minute of the pasta's cooking time, reserve 1/2 cup of the cooking water. Then, add spinach to the pot, stirring well and pushing the leaves down to submerge them in the water.
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