Not a true peppercorn, but rather the dried berry/seed of a deciduous prickly ash tree. The 3-4 mm berry has a rough reddish brown shell that is split open and a black seed inside. The black seed is bitter and can be discarded. The red shell can be added whole to stewed dishes or ground to a powder and used a seasoning. The spice has a unique aroma and flavor that is not as pungent as black pepper and has slight lemony overtones. Szechuan peppercorns are one of the five spices in Chinese five-spice powder. Called sansho in Japan, they are used in the spice mixture shichimi togarashi, or Japanese seven-spice seasoning.
The spice is best purchased whole and ground as needed. Can sometimes be found in bulk at health food and gourmet stores.
They are generally used in either of two ways: For stir fried dishes: heat a dry skillet (no oil) on medium flame and add the Szechuan peppercorns. Toss and stir until they start to smoke a little. (Don't burn them). When cool enough to work with grind them in a spice mill, mortar & pestle or pepper grinder. (an electric coffee grinder can be used for grinding spices). Use whatever the recipe calls for and freeze the rest in a plastic container. For stews: add them whole along with the other seasonings and remove before serving.