Whisk together soup, sour cream, mushrooms, parsley, & salt & pepper to taste.
Divide chicken into 2 gallon size freezer bags (be sure to label bags first!) Divide soup mixture into bags and make sure soup mixture covers all chicken; freeze until needed.
On cooking day, place frozen chicken directly into crockpot. Cook on high 5-6 hours, or on low 7-8 hours.
Optional! If desired, serve over a bed of egg noodles.