Awesome Pulled Pork BBQ

Name: Awesome Pulled Pork BBQ
Ingredients: 1 (5 pound) boneless pork loin roast; 1 pinch garlic powder, or to taste; 1 pinch poultry seasoning, or to taste; salt to taste; ground black pepper to taste; 1 large onion, quartered; 1 apple, cored and quartered; 3 stalks celery; 1 (14.5 ounce) can chicken broth; 0.5 cup butter; 2 cups chopped celery; 1.5 cups chopped onion; 4 cups ketchup; 2 cups water; 0.66666668653488 cup cider vinegar; 0.5 cup brown sugar; 0.25 cup Worcestershire sauce; 2 tablespoons prepared mustard; 1 tablespoon liquid smoke flavoring; 1 tablespoon garlic powder