Boil water and cook fettuccine according to package directions.
While pasta is cooking, in a sauce pan melt butter over medium heat. Add cream and whisk together and let it simmer. Cook until sauce has reduced a little, about 5 minutes.
Take off heat and stir in the Parmesan cheese.
Just before the pasta is ready, reserve about 1/4 c. of pasta water - this helps to thin the sauce so it won't clump up at the end. Drain pasta.
Pour alfredo sauce over pasta. Toss the fettuccine with some tongs to get the noodles fully coated in the sauce. If the sauce gets thick or clumpy add a little of the pasta water.
Serve immediately and enjoy!