Chicken and Sausage Gumbo

Name: Chicken and Sausage Gumbo
Ingredients: 12 ounces andouille sausage links; 1 pound chicken breast or thighs; 2 tablespoons peanut, corn or vegetable oil, divided; salt and pepper; 1 medium onion, diced (about 2 cups); 2 stalks celery, diced (about 1 cup); 1 green bell pepper, diced (about 1 cup); 4 cloves garlic, minced (about 2 tablespoons); 1/4 cup flour; 1 teaspoon thyme; 1 bay leaf; 1/4 teaspoon cayenne pepper; 4 cups chicken stock; 15 ounce can tomatoes; 1 cup chopped parsley; 12 ounces (3/4 pound) whole okra, fresh or frozen*; 1 teaspoon file powder**; Cooked rice or cornbread for serving