In a large pot, heat water and salt over high heat until boiling. Add the fettuccine pasta and cook according to the package instructions. Reserve about 1 cup of the pasta water.

In a large skillet, melt the butter over medium heat. Stir in the garlic and cook for 1 to 2 minutes. Stir in the heavy cream. Let the cream reduce and cook for 5 to 8 minutes, stirring frequently.

Stir in the Parmesan and Romano cheeses until smooth and the cheeses have melted. If the sauce is too thick to pour, stir in some of the reserved pasta water to thin out slightly.

Pour the sauce over the fettuccine pasta and toss to coat well. Sprinkle with additional cheeses, pepper, smoked paprika and parsley, if using, and serve immediately.