In a large skillet, cook bacon over medium heat until crisp. Using a slotted spoon, remove to paper towels to drain, reserving 1 tablespoon drippings. In same skillet, saute onions and garlic in drippings until tender. Pour into a Dutch oven or soup kettle. Add the tomatoes, consomme and water. Cover and bring to a boil; add the leeks, carrot and okra. Reduce heat; simmer, uncovered, for 25 minutes, stirring occasionally. Add the shrimp, crab, salt and cayenne; simmer, uncovered, for 5 minutes. In a small bowl, combine flour and cold water until smooth. Stir into gumbo mixture. Bring to a boil; cook and stir for 2 minutes or until slightly thickened. Stir in parsley and reserved bacon. Serve immediately with rice. Yield: 16-20 servings (about 5 quarts).