| Preheat oven to 350 degrees F. Place chicken in a roasting pan and season generously inside and out with salt and pepper. Sprinkle inside and out with onion powder. Place 3 tablespoons butter in the chicken cavity along with the celery. Arrange dollops of the remaining butter around the chicken's exterior and under the skin. Bake uncovered 1 hour 15 minutes in the preheated oven, to a minimum internal temperature of 180 degrees F. Remove from heat and baste with melted butter and drippings. Cover with aluminum foil, and allow to rest about 30 minutes before serving. | 
