Heat olive oil in a large pan over medium heat. Add chicken, mushroom, onions and garlic. Sauté until no pink remains on the chicken, about 10 minutes.
In another small pot, add cream, wine, salt and pepper and heat to a boil over medium-high heat. Mix together cornstarch and water and add to mixture. Boil until the liquid is reduced to about half and is thickened to your desired consistency.
Add cream mixture to the chicken and mix together.
Add parsley and season with salt and pepper. Serve over a bed of egg noodles.