In a large pot of salted boiling water, cook the fettuccine or spaghetti according to package instructions until al dente. Reserve 1 cup of pasta water before draining.
In a large skillet, melt the butter over medium heat until it begins to foam. Add the lemon zest and sauté for about 1 minute until fragrant.
Reduce the heat to low and add the ricotta cheese to the skillet. Stir until creamy and well combined with the butter.
Add the drained pasta to the skillet, along with the reserved pasta water (start with 1/2 cup and add more as needed for desired creaminess). Toss until the pasta is well coated with the ricotta sauce.
Stir in the lemon juice and grated Parmesan cheese, mixing well. Season with salt and pepper to taste.
Plate the pasta and garnish with additional lemon zest and fresh herbs like basil or parsley for a pop of color and flavor.