Flé powder, (or Gumbo filé powder) is a necessity for cooking authentic Cajun cuisine. It is also essential in Creole cooking.  Made from the powdered leaves of the sassafras tree, Filé has a cooling smell, reminiscent of eucalyptus crossed with juicy fruit gum. Filé powder is used for its unique flavor and aroma as much as it is used as a thickening agent for Soups and stews, especially Gumbo.