Add cubed chicken into a lightly greased slow cooker.
Season the chicken with salt, pepper and onion powder.
Add in chicken stock, sour cream, Dijon, and Worcestershire sauce. Mix to incorporate.
Add the mushrooms, then place chunks of softened cream cheese on top of the mixture in the slow cooker. Set it on LOW for 6 hours.
Stir well to mix everything and to help break up the cream cheese. The chicken will start shredding at this point but you may need to shred it lightly with a fork.
Add in the egg noodles and cover the crock. Allow them to cook for 20 minutes, stirring halfway through to ensure all noodles get cooked evenly.
Serve immediately with freshly chopped parsley.
