Boil pasta in salted water until al dente according to package directions. Reserve some pasta cooking water before draining. Properly salted water ensures flavorful pasta.
Heat olive oil in a large skillet and sauté garlic gently until fragrant. Avoid browning garlic since it becomes bitter. This step builds the flavor foundation of the sauce.
Add heavy cream to the skillet and simmer briefly to thicken slightly. Stir occasionally to prevent sticking. The sauce should become smooth and velvety.
Stir in lemon zest, lemon juice, and Parmesan cheese. The cheese melts and thickens sauce naturally. Adjust lemon level depending on preferred brightness.
Add cooked pasta directly into sauce along with reserved pasta water. Toss until pasta is fully coated. Pasta water helps emulsify sauce for a silky texture.
Finish with parsley, black pepper, and extra Parmesan. Serve immediately while creamy and hot. Garnishes add color and fresh flavor contrast.