Step 1: Cook the pasta according to package directions in a large pot of salted boiling water until al dente. Before draining, reserve about 1 cup of the starchy pasta water. Drain the pasta and set aside.
Step 2: While the pasta cooks, heat the olive oil in a large skillet or pan over medium heat. Add the minced garlic and sauté for 1 minute until fragrant, being careful not to burn it.
Step 3: Add the fresh baby spinach to the skillet. Cook, stirring occasionally, until the spinach wilts down, about 2-3 minutes.
Step 4: In a medium bowl, combine the ricotta cheese, lemon zest, 2 tablespoons of lemon juice, 1/4 cup Parmesan cheese, 1/2 teaspoon salt, and 1/4 teaspoon black pepper. Stir until well combined.
Step 5: Add the drained pasta to the skillet with the wilted spinach and garlic. Remove the pan from the heat.
Step 6: Spoon the ricotta mixture over the pasta. Add about 1/4 cup of the reserved pasta water. Toss gently to combine, ensuring the sauce evenly coats the pasta. Add more pasta water, a tablespoon at a time, if the sauce is too thick.
Step 7: Taste and adjust seasonings, adding more lemon juice, salt, or pepper as needed. Serve immediately, garnished with extra grated Parmesan cheese and a sprinkle of fresh black pepper.