How to Make It
Pick crabmeat, removing any bits of shell.
Remove shrimp shells and heads. Cover and refrigerate shrimp, and place shells and heads in a large stockpot. Add 8 cups water and a generous pinch of salt, and bring mixture to a boil over high heat. Reduce heat to medium-low, and simmer, partially covered, 1 hour. Cool 30 minutes; pour stock through a fine wire-mesh strainer, and reserve for use in Step Discard shells and heads.
Heat 2 Tbsp. oil in a large heavy skillet over medium heat, and add okra. Sprinkle with 1/2 tsp. salt, and sauté 10 minutes. Set aside okra, and wipe out skillet. Heat another tablespoon of oil in skillet over medium-high heat, and sauté andouille about 8 minutes or until brown. Set aside.
Heat remaining 3 Tbsp. oil in a large heavy pot over high heat. Add flour, reduce heat to medium, and cook, stirring constantly, about 10 minutes or until roux is a medium-to-dark brown. Add yellow onions, celery, and bell pepper, and sauté 4 to 5 minutes or until vegetables begin to soften. Add garlic and 1/2 cup green onions, and cook 3 more minutes. Stir in tomato paste and next 7 ingredients. Stir in tomatoes and 1/3 cup of their liquid; gradually stir in shrimp stock. Add reserved sausage and okra. Bring to a boil over high heat, and cover. Reduce heat to medium-low, and simmer 30 minutes.
Stir in shrimp and remaining green onions, and simmer 3 minutes. Stir in crabmeat, oysters, and parsley, and simmer 1 minute. Remove from heat. Taste and add salt, if desired. Serve over rice.
* Fresh okra may be substituted for frozen.