Make sure to carefully follow each step of the instructions for the best results :
- Boil the pasta.
Bring a large pot of well-salted water to a boil and cook the pasta until just al dente according to the package directions. Before draining, reserve about 1 cup of pasta water. Drain the pasta and toss lightly with the olive oil to keep it from sticking while you finish the sauce. - Sauté the garlic.
While the pasta cooks, melt the butter in a large skillet over medium heat. Add the minced garlic and cook for about 30 to 60 seconds, stirring often, until fragrant and lightly softened. Keep the heat moderate so the garlic turns sweet and aromatic instead of browning too quickly. - Build the creamy sauce.
Pour in the heavy cream and stir gently to combine with the garlic butter. Let it warm for 2 to 3 minutes until it starts to gently simmer around the edges, then season with black pepper, salt, and red pepper flakes if using. This short simmer helps the sauce thicken slightly before the cheese goes in. - Add the Parmesan.
Lower the heat and gradually stir in the freshly grated Parmesan cheese a little at a time. Stir continuously so it melts smoothly into the sauce without clumping. If the sauce feels too thick, add a splash of the reserved pasta water until it reaches a silky, glossy consistency. - Toss and serve.
Add the cooked pasta to the skillet and toss until every strand is evenly coated in the creamy garlic Parmesan sauce. Let it cook together for 1 minute so the pasta absorbs some of the flavor. Finish with chopped parsley and extra Parmesan, then serve immediately while hot and creamy.