Bring a large pot of heavily salted water to a boil over high heat.
Cook the fettuccine to just al dente, about 8 minutes. Reserve a half cup of the pasta cooking water, and drain the pasta.
Bring the pasta water and the butter to a boil in a 10" skillet over medium high heat. Add the cooked pasta, reduce the heat to medium-low, and sprinkle the cheese over the top, using kitchen tongs or two spoons to toss the mixture gently, until all the pasta is coated in a smooth sauce. Add black pepper, and taste for salt to add as needed. Serve and enjoy!