Start by making a roux by melting the butter over medium heat then once melted adding in the flour and whisking together until turns a rich mahogany brown color, about 20-30 minutes. Once the roux forms a smooth, mahogany brown mixture, remove from the heat and continue to whisk until it stops cooking.
Place celery, onion, green bell pepper, and garlic into the work bowl of a food processor and pulse until finely chopped. Add the vegetables and sausage into the roux and bring the mixture to a simmer over medium-low heat. Cook until the vegetables are tender. Remove from heat, set aside.
Bring the water and beef bouillon cubes to a boil in a large soup pot. Whisk until the cubes dissolve, then whisk the roux mixture into the boiling water. Reduce the heat to a simmer. Add in the sugar, salt, hot pepper sauce, Cajun seasoning, bay leaves, thyme, diced tomatoes, and tomatoes sauce. Simmer the soup over low heat for 1 hour.
While the soup simmers, melt the remaining butter in a skillet and cook the okra with vinegar over medium heat for 15 minutes. Stir in the okra into the simmering gumbo.
Then add in the crab meat, shrimp, and Worcestershire sauce and simmer until the flavors have blended, another 45 minutes. Stir in the cornstarch just before serving.
Serve hot over white rice. Season with salt and black pepper to taste.