Alfredo
Alfredo is an Italian sauce made from heavy cream, butter, parsley, and minced garlic. It is most often served on fettuccine noodles.There are many modifications to the basic Fettuccine Alfredo. A popular one is adding chicken. Cheeses or vegetables are also often added to the recipe. When it's bacon that is added then it's called à la Carbonara. It can also be served on many different types of pasta. There are many other uses of Alfredo sauce, it can be used to marinate meats.
Because of the butter and heavy cream, Alfredo is one of the most unhealthy sauces. It is sometimes referred to as "heart-attack-on-a-plate", but there are also low fat versions available.
A popular variation to Alfredo uses a Asiago/Parmesan/Romano cheese combination. Commonly, a cup of flour is added to a large batch of the cheese mix so it thickens up more quickly, instead of needing to add extra cheese to absorb some of the light fluid. This helps the Alfredo maintain some of the creamy texture without adding an excessive amount of cheese.
Alfredo sauce was invented in Rome in the 1920s by restaurant owner Alfredo di Lello. Earlier versions had existed in Italy for many years, but it is not a traditional Italian dish. Fettuccine Alfredo became extremely popular, and his restaurant attracted many celebrities. Two of these were Mary Pickford and Douglas Fairbanks, who fell in love with the dish while on their honeymoon in 1927. One their return to the United States asked for the same recipe, and thus introduced it to the New World. Since then Alfredo has been far more popular in the United States than in Italy, where it is mostly served to tourists.