This pepper is native to the Sichuan region of China. It is now cultivated throughout China, Korea, Mongolia, Nepal and Bhutan. More than 2,000 years ago it was mixed with plaster to perfume the walls of imperial palaces. Sichuan peppercorn is now a key ingredient in many kinds of Chinese cooking. That numbing sensation you get from an excellent Sichuan dish comes from this pepper. Toast Sichuan peppercorns or toss them into vegetable, seafood or meat dishes. These peppercorns become hottter as they cook.