01 - Bring a large pot of salted water to a boil. Cook pasta according to package instructions until al dente. Reserve 1/2 cup (120 ml) pasta water, then drain the pasta.
02 - Melt butter in a large skillet over medium heat. Add minced garlic and sauté for 1–2 minutes until fragrant without browning.
03 - Pour in heavy cream and bring to a gentle simmer. Cook for 2–3 minutes, stirring occasionally.
04 - Add grated Parmesan, salt, black pepper, and red pepper flakes if using. Stir until cheese melts and sauce is smooth.
05 - Add drained pasta to skillet and toss to coat evenly in sauce. Adjust consistency by adding reserved pasta water a little at a time if necessary.
06 - Remove from heat and stir in most of the chopped parsley, reserving some for garnish.
07 - Plate immediately and top with remaining parsley and extra grated Parmesan cheese.