Shrimp and Cod with Tarragon Broth and Croutons

Name: Shrimp and Cod with Tarragon Broth and Croutons
Ingredients: 2 tablespoons butter; 1 onion, chopped; 2 ribs celery, chopped; 2 cloves garlic, minced; 1 teaspoon salt; 1/2 cup dry white wine; 1 1/4 teaspoons dried tarragon; 1 cup bottled clam juice; 1 2/3 cups canned diced tomatoes with their juice (one 15-ounce can); 3 cups water; 2 cups 1/2-inch bread cubes cut from good-quality white bread; 2 1/2 tablespoons olive oil; Fresh-ground black pepper; 1/3 cup chopped fresh parsley; 3/4 pound boneless, skinless cod fillet, cut into approximately 1-by-1/2-inch strips; 3/4 pound medium shrimp, shelled and halved lengthwise