Cooking Turkey for Beginners - An Easy Step-by-Step Turkey Recipe

12 to 24 lb Turkey, thawed
2 tbsp kosher salt
1 tbsp black pepper
1 tbsp poultry seasoning (fresh, not from 1997)
2 onions, cut in large pieces
3 ribs celery, cut in large pieces
2 carrots, cut in large pieces
3 rosemary sprigs
1/2 bunch sage
1 stick butter, or this seasoned butter recipe