From Saveur magazine. My husband wants to try this, so I'm posting it before we lose the magazine. Looks like it'd be neat to try. The article says "the FDA banned safrole - a naturally occurring compound found in the oil of sassafras root bark - for commercial use, but it is still realitively easy to find sassafras in health food stores..." Makes 4 liters. Dried birch bark and dried sarsaparilla root aren't recognized ingredients, so I listed sugar instead with the real ingredients in parenthesis, just so they would be in the list of ingredients.