Fil? (Fee-lay) - the finely ground dried sassafras leaves used to thicken and add exotic flavor to gumbo. In the month of August, break branches from a sassafras tree. Hang branches upside down to dry in a shaded, ventilated place for about 2 weeks. Flavor is enhanced if put in bright sunlight for 1-2 hours before grinding into powder. Use a mill and grind into a fine powder. Store in tightly closed dark jars in a cool place. NOTE: To some extent rubbed sage can be substituted for fil?, although the flavor will not quite be the same.