Bring a large pot of water (about 4–5 liters) to a rolling boil. Add 1 tablespoon salt. Add 12 oz dried fettuccine and cook according to package instructions until al dente (usually 8–11 minutes). Stir occasionally to prevent sticking.

Reserve 1 cup of the starchy pasta cooking water before draining. Drain the pasta and set aside in the colander while you finish the sauce.

Alfredo Sauce

Sweat garlic in butter

In a large wide skillet or sauté pan over medium heat, add 6 tablespoons unsalted butter. When butter is melted and begins to foam (but not brown), add the 2 minced garlic cloves and cook 30–45 seconds until fragrant, stirring constantly so garlic does not brown.

Add cream and milk

Pour in 1 cup heavy cream and 1 cup whole milk. Increase heat slightly to bring the mixture to a gentle simmer (small bubbles at the edge). Do not boil vigorously. Simmer 3–4 minutes to slightly thicken, stirring occasionally.

Incorporate cheeses

Lower heat to medium-low. Add 1.5 cups freshly grated Parmesan cheese in two additions, stirring until melted and smooth after each addition. If using 2 oz cream cheese, cut into small pieces and whisk into the sauce until fully incorporated to make the sauce richer and silkier.

Season the sauce

Season with 1 teaspoon salt, 1/2 teaspoon freshly ground black pepper, and 1/8 teaspoon freshly grated nutmeg (optional). Taste and adjust seasoning gently — Parmesan is salty, so be conservative with salt.

Adjust consistency

If the sauce seems too thick, whisk in up to 1 cup reserved pasta cooking water, a few tablespoons at a time, until the sauce reaches a glossy, clingy consistency that will coat the pasta (you may not need the full cup). Keep the sauce warm over the lowest heat.

Finishing & Garnish

Toss pasta with sauce

Add the drained pasta directly to the skillet with the sauce (or return the pasta to the pot and pour sauce over it). Add 1 tablespoon unsalted butter (optional) and toss or gently stir for 1–2 minutes so the pasta is fully coated and the sauce adheres. If the sauce tightens up, add a splash of reserved pasta water to loosen.

Remove from heat. Taste and adjust seasoning with additional black pepper or a pinch of salt if needed.

Serve

Divide the Alfredo pasta among warm plates, sprinkle with 2 tablespoons finely chopped fresh parsley and 1/4 cup extra grated Parmesan. Serve immediately so the sauce remains silky.