The key is the chicken. You have to have great chicken, else you have Alfredo sauce and fettuccine pasta with protein chunks. Add a contrasting flavor in your seasoning of choice, and learn how to cook some mean chicken.
I prefer boneless, skinless chicken breasts, fresh, not frozen. They cook way better when they are fresh. Also, get a simple Alfredo sauce. No need for a garlic or mushroom, unless you want to add that from fresh ingredients.
First, get some extra virgin olive oil in a pan. Just a light coat of the bottom, we aren't deep frying the chicken. You want the pan hot enough for a sear, or a quick, high-heat cooking of the outside of the chicken, in order to preserve the natural juices of the chicken. The seasoning you choose is important. I use a combination of all-purpose season (Lawry's) and a cajun seasoning (Tony Chachere's) and a sprinkle of garlic salt. Give a good coating of the all-purpose seasoning on one side of the breast. Add a touch of the cajun seasoning and garlic salt, and lay that side down in the pan, and season the other side.
I recommend covering the pan, that way the entire chicken breast heats up, making it easier to cook thoroughly. The sides of the breast will begin to white, and a few minutes after that, the first side should be ready. Flip it and repeat on the other side, covering again as to get the internal temperature up.
Preheat your oven to about 350. After a few minutes with the chicken, pull it off the pan and onto a baking sheet in the oven for about 5-7 minutes. This will keep the inside cooking without burning your outsides.
Now with all that goodness still in your pan, dump your Alfredo sauce in, along with an equal amount of milk, and turn your heat down to about low-medium (4-5). Mix until your oil and sauce come together, although they will separate some once you stop mixing. You can add your cooked noodles in the sauce as well.
If you prefer a lighter taste, use a lighter olive oil. Extra virgin does wonders to the chicken that the light stuff can not.
Now, pull your chicken, and give it a stab in the thickest part of the thickest piece. If there is not juices gushing out then you should be ok. Now slice up your breasts into pieces you see fit. If you see parts of the chicken not done, don't panic. Just slip it back in the oven for a few minutes.
During the chicken cooking process, add some freshly pressed garlic and mushrooms for some added flavor. Before adding the sauce to the leftover oil, get your garlic and mushrooms sauteed, and then your mushrooms will absorb the garlic and oil and really kick with the sauce.
You can substitute the thinly cut breasts, but they tend to overcook for me before the outside gets a thin layer of golden color.