Things You'll Need
File powder is ground from the dried leaves of a Sassafras tree. The Choctaw Indians taught early Cajuns about file powder, which they used to thicken soups. In Louisiana today, file powder is primarily used to thicken a traditional stew called gumbo, a spicy, rich dish of gravy with meats and seafood. File powder can also be sprinkled on gumbo at the table. Making the powder is quite simple; you need to have access to some Sassafras branches and some time.
Cut the Sassafras branches in the fall, before they have a chance to change color. Place them in a cool, dark place to dry. You do not want the branches to dry in sunlight because it will affect the color of the leaves as they dry.
Remove the leaves from the stem when they are completely dry. Crush by hand. Grind the crushed leaves in a blender until a fine powder forms.
Sift the powder to remove any large pieces. Store in an airtight container. Homemade file powder keeps longer if refrigerated and kept dry.