01 - Bring a large pot of salted water to a boil. Cook the fettuccine until al dente according to package instructions. Reserve 1/2 cup of pasta water, then drain the pasta.
02 - Melt the unsalted butter in a large skillet over medium heat. Add minced garlic and sauté until fragrant, about 1 minute.
03 - Pour in heavy cream and bring to a gentle simmer. Cook, stirring frequently, for 2 to 3 minutes until slightly thickened.
04 - Reduce heat to low. Stir in grated Parmesan, sea salt, black pepper, and nutmeg if using. Stir until the cheese melts and sauce is smooth.
05 - Add drained fettuccine to the skillet and toss to coat evenly. Gradually add reserved pasta water as needed to achieve desired sauce consistency.
06 - Plate immediately and garnish with chopped parsley and extra Parmesan if desired.