Sichuan or Szechuan Peppercorns are a unique spice. With a slightly lemony and floral overtone it is not hot or pungent like black pepper. It is a staple in traditional Chinese cuisine. Its appearance is close to black peppercorns. Ideally, you should toast your peppercorns prior to grinding to bring out their special fragrance.
Here's a recipe using Sichuan Peppercorns: