The next time I make this, I think I would do the sauce alfredo style rather than tossing it together in the pot. I find that cheese melts more smoothly this way.
This recipe is adapted from my Bon Appetit cookbook.
1/2 lb spaghetti
1 cup freshly grated Parmesan cheese plus extra for serving
1/4 cup (1/2 stick) unsalted butter, softened
freshly ground black pepper
Cook spaghetti in a large pot til just al dente. Drain, reserving 1 cup cooking liquid. Return spaghetti to pot. Stir in 1/4 cup reserved cooking liquid, cheese and butter.
Toss mixture over medium heat til cheese melts and sauce coats pasta, adding more reserved cooking liquid if needed. Season generously with salt and pepper.
I served this Parmesan and a slice of toasted rustic wheat bread.