Smothered Chicken and Biscuits

Name: Smothered Chicken and Biscuits
Ingredients: 2 tablespoons extra-virgin olive oil; Salt and freshly ground black pepper; 1 whole chicken fryer, cut into pieces; 2 cups all-purpose flour, plus more for work surface; 1 tablespoon Paula's House Seasoning, recipe follows; 2 ribs celery, chopped; 1 onion, chopped; 2 scallions, chopped; 1/2 cup water; 2 cups self-rising flour, plus more for work surface; 1 1/2 tablespoons salt; 1 tablespoon sugar; 1/2 cup shortening; 1 cup milk; 2 tablespoons butter; 1 cup salt; 1/4 cup black pepper; 1/4 cup garlic powder