As the pasta cooks, in a large pan over medium heat, melt the butter until it becomes golden and develops a nutty aroma, 2-3 minutes. Once the pasta is cooked and drained, take the warm bowl or platter from the oven. Place butter pats into the warm serving dish, then place the pasta on top. Pour in 1/2 of the reserved water, sprinkle half of the cheese over the fettuccini and toss for 1 minute. Add more cheese, continuing to toss for an additional 2 minutes until the pasta is uniformly coated and the cheese has melted into a luscious sauce. If too thick, thin out with remaining water. Serve immediately, garnishing with additional Parmesan and black pepper if desired.