Step 1 Whisk together flour and 3/4 cup bacon drippings in a large, heavy saucepan over medium-low heat until smooth. Cook roux, whisking constantly, until it turns a rich mahogany brown color. This can take 20 to 30 minutes; watch heat carefully and whisk constantly or roux will burn. Remove from heat; continue whisking until mixture stops cooking.
Directions Gumbo:
Step 1 Place celery, onion, green bell pepper, and garlic into the work bowl of a food processor; pulse until all vegetables are very finely chopped. Stir vegetables into the roux and mix in sausage. Bring mixture to a simmer over medium-low heat; cook until vegetables are tender, 10 to 15 minutes. Remove from heat and set aside.
Step 2 Combine water and beef bouillon cubes in a large Dutch oven or soup pot and bring to a boil over medium-high heat. Stir until bouillon cubes dissolve, then whisk roux mixture into the boiling water.
Step 3 Reduce heat to a simmer, and mix in sugar, salt, hot pepper sauce, Cajun seasoning, bay leaves, thyme, stewed tomatoes, and tomato sauce. Simmer soup over low heat for 1 hour; mix in 2 teaspoons of file gumbo powder at the 45-minute mark.
Step 4 Meanwhile, melt 2 tablespoons bacon drippings in a skillet over medium heat. Add okra and vinegar and cook for 15 minutes; remove okra with a slotted spoon and stir into the simmering gumbo.
Step 5 Mix in crabmeat, shrimp, and Worcestershire sauce; simmer until flavors have blended, 45 more minutes. Stir in 2 more teaspoons of file gumbo powder just before serving.