Pulled Chicken Gumbo

Name: Pulled Chicken Gumbo
Ingredients: 4 tablespoons vegetable oil; 6 chicken thighs or leg quarters; Kosher salt and freshly ground black pepper; 6 tablespoons all-purpose flour; 3 cloves garlic, minced; 2 ribs celery, chopped; 2 scallions, thinly sliced, green and white parts kept separate; 1 small green bell pepper, chopped; 1 onion, chopped; 4 cups chicken stock; 1 tablespoon seafood seasoning, such as Old Bay