Gumbos vary tremendously from Region to region, from family to family, from pot to pot. In the 19th century, for example, the Creole people of the city thickened their Gumbos with okra or, in winter, when okra wasn’t available, with the ground leaves of the sassafras tree, known as filé powder; these days, either or both are used. In Cajun country, meanwhile, just outside New Orleans, they use a