Crawfish Étouffée

Name: Crawfish Étouffée
Ingredients: 3 tablespoons butter; 1 cup diced onion; 1/2 cup diced green bell pepper; 1/2 cup chopped celery; 1 tablespoon Cajun Spice Seasoning; 2 tablespoons all-purpose flour; 1/2 cup diced tomatoes; 2 cups chicken stock; 1/2 teaspoon Worcestershire sauce; 1 dash hot sauce (Tobasco); 12 ounces cooked crawfish (or substitute with langostino); 1/2 teaspoon salt; 1/4 cup sliced green onions; 1 bay leaf; cooked medium or long grain white rice (for serving)