Sichuan peppercorn come from a tree known as the prickly ash, and there are many different species of this tree. The peppercorn produced by these trees are classified by size and color. In Sichuan cuisine the red and green peppercorns are primarily used; these are often referred to as Rattan peppers.
The finely ground powder is one of the key ingredients of the famous Sichuan “Five Spice Powder”. But uses for Rattan goes far beyond its role in food. Peppercorn is also used in traditional Chinese medicine, it is believed to aid in the regulation of blood pressure, to help increase appetite, and also reduce the stomach indigestion.
The unique aroma of the peppercorn hides more than meets the senses and the flavor is more dynamic than black, white, or chili peppers. They are not spicy or pungent but instead have a characteristic numbing taste that makes it fall into the list of strong flavored spices. According to Harold McGee in On Food and Cooking: "They produce a strange, tingling, buzzing, numbing sensation that is something like the effect of carbonated drinks or of a mild electric current.” The Sichuan peppercorn goes very well with chili peppers, and it is this combination that makes Sichuan hot pot popular all over the world.