Wash the okra in cool water. Trim the stems and tips and cut into 1/4-inch rounds.
Heat the olive oil in a large pot over medium-high heat. Add the sausage and cook, stirring often, to render out the fat, about 5 minutes. Add the okra and cook, stirring constantly, for 10 to 12 minutes, or until most of the slime disappears. Add the tomatoes, onions, bell peppers, celery, and garlic and cook, stirring often, for 10 minutes, or until the okra and other vegetables are soft and the slime has completely disappeared. Add the salt, cayenne, bay leaves, thyme, and Shrimp Stock.
Season the shrimp with the Essence and set aside. Stir the pot and bring the contents to a boil. Reduce the heat to medium and simmer, uncovered, for 15 minutes. Add the shrimp and cook, stirring occasionally, for 30 minutes.
Remove the bay leaves, garnish with the parsley and green onion tops, and serve in shallow bowls over white rice.
Makes 3 quarts, 10 to 12 servings