Bring a large pot of salted water to a boil. Add the fettuccine and cook according to package instructions until al dente. Drain and set aside.

In a saucepan over medium heat, melt the butter. Add the minced garlic and sauté until fragrant, about 1 minute.

Stir in the heavy cream, lemon zest, and lemon juice. Bring to a simmer and cook for about 3-4 minutes, stirring occasionally.

Add the grated Parmesan cheese, salt, and pepper. Stir until the cheese is melted and the sauce is smooth.

Add the cooked pasta to the sauce and toss to coat evenly. Serve immediately, garnished with chopped parsley and lemon slices.