Spray the ceramic insert of a slow cooker with some non-stick cooking spray.

Dump the stuffing mix into a bowl. Add the onion, celery, cream of chicken soup, dried cranberries, and chicken broth, stirring everything together completely. Spoon this mixture into the slow cooker,

Sprinkle the sage over top.

Lay the chicken breasts on top of everything, seasoning them with some salt and black pepper. Cover and cook on low for 4 ½ hours, or until the chicken is cooked through.

Shred the chicken or slice into pieces. Stir everything together and serve immediately with your favourite gravy, hot and ready to ladle over top!