01 - Bring a large pot of salted water to a boil. Add the pasta and cook until al dente according to package directions. Reserve ½ cup pasta water, then drain.
02 - Heat butter and olive oil in a large skillet over medium heat. Add minced garlic and sauté for 1 to 2 minutes until fragrant, avoiding browning.
03 - Pour in heavy cream, stirring to combine. Simmer gently for 3 to 4 minutes until sauce slightly thickens.
04 - Incorporate Parmesan cheese, black pepper, salt, and red pepper flakes (if using). Stir until cheese melts and sauce smooths.
05 - Add drained pasta to skillet and toss to coat evenly. Gradually add reserved pasta water as needed to achieve preferred sauce consistency.
06 - Stir in most of the chopped parsley, reserving some for garnish. Adjust seasoning to taste.
07 - Plate immediately, topped with additional Parmesan and remaining fresh parsley.