01 - Bring a large pot of salted water to a boil. Cook the fettuccine until al dente following package instructions. Reserve ½ cup of the pasta cooking water, then drain the pasta.
02 - Melt butter in a large skillet over medium heat. Add minced garlic if using, and sauté for 1 minute until fragrant.
03 - Pour in heavy cream and bring to a gentle simmer. Cook for 2 to 3 minutes, stirring occasionally.
04 - Reduce heat to low and gradually whisk in Parmesan cheese until the sauce is smooth and creamy. Season with salt and freshly ground black pepper to taste.
05 - Add drained fettuccine to the skillet. Toss to coat evenly, adding reserved pasta water incrementally to achieve desired sauce consistency.
06 - Plate immediately, garnished with chopped parsley and extra Parmesan cheese if desired.