1.Spray The Crock Of A Slow Cooker With Non-Stick Cooking Spray. Place Chicken Breasts In Crock. Combine Italian Dressing Mix, And Water In A Small Bowl. Pour Over Chicken; Sprinkle With Garlic, Cover, And Cook On Low 4 Hours. 2.After 4 Hours, Whisk Softened Cream Cheese And Cream Of Chicken Soup Together In A Bowl. Pour Over Chicken; Stir In Mushrooms. Cover And Cook On Low For 1 Additional Hour. 3.Fill A Large Pot With Lightly Salted Water And Bring To A Rolling Boil Over High Heat. Once The Water Is Boiling, Stir In The Spaghetti, And Return To A Boil. Cook The Pasta Uncovered, Stirring Occasionally, Until The Pasta Has Cooked Through, But Is Still Firm To The Bite, About 12 Minutes. Drain Well In A Colander Set In The Sink. 4.To Serve, Spoon Chicken And Sauce Over Hot Cooked Pasta And Sprinkle With Parsley.