Bring a large pot of salted water to a boil. Cook the fettuccine according to the package instructions until al dente. Reserve 1 cup of pasta water, then drain the pasta and set it aside.

In a large skillet over medium heat, melt the butter until bubbly. Add the minced garlic and sauté for about 1 minute, until it becomes fragrant but not browned.

Pour the heavy cream into the skillet and let it simmer for 5 to 8 minutes. Stir occasionally until the mixture starts to thicken slightly.

Reduce the heat to low and whisk in half of the Parmesan cheese. Continue whisking until the sauce is smooth and creamy.

Add the drained fettuccine to the sauce and toss gently to coat the pasta evenly. If the sauce is too thick, gradually add reserved pasta water until you reach your desired consistency.

Sprinkle in the remaining Parmesan cheese and season with salt and pepper to taste. Serve the Fettuccine Alfredo immediately, garnished with chopped parsley if desired.