Have you ever cooked a whole turkey breast in the crockpot? I did, for the first time, this weekend, and I can tell you I will be doing it again and again. It was super tender without being dried out (in fact it was quite moist and flavorful) and it makes enough broth to make a wonderful gravy too!
Wash and pat dry your turkey breast. Trim the meat so that it will fit into the crockpot ( I had to remove a little of the rib bones to get it to fit into my crockpot).
Coat the surface of the turkey with minimal butter and rub the dry onion soup mix and pepper all over the surface of the turkey. Put the chopped celery into the bottom of the crockpot and add ½ cup of chicken broth.
Lay the turkey breast (breastbone side down) on top of the chopped celery. Cook on high one hour, then on low for 7 hours.