Cook fettuccine in a pot of boiling, salted water until al dente. Reserve 3/4 cup cooking water, then drain pasta.

Pat dry the shrimp. Season them with salt and pepper.

Melt butter in a skillet over medium heat. Add the shrimp and cook just until pink, about 3 minutes. Remove from the skillet.

Add the garlic and sauté for just 30 seconds, stirring continuously, to avoid burning. Pour in the heavy cream and bring to a simmer, just lightly bubbling. Simmer for about 5 minutes, until the bubbles in the cream become thicker, this is a sign that it has reduced enough.

Adjust the heat to low. Add the cheese and whisk until combined.

Add cooked fettuccine and 1/4 cup of the reserved pasta water to the sauce. Toss and stir until the sauce is creamy and velvety. You will likely need to add more cooking water to keep it silky. After adding the water, taste the pasta and season with salt and pepper, to your liking. It takes more salt that you might think to season it properly.

Serve with the parsley and some additional Parmigiano cheese on top.