Kung Pao, or Kung Po, beef is a westernized version of the classic Szechuan dish called Kung Pao chicken. In the original Chinese version, chicken is stir-fried with vegetables, fresh peanuts or cashews, chili peppers and Szechuan peppercorns. Western versions may substitute beef, pork, seafood or tofu for the chicken.
The westernized version of a Kung Pao-style dish typically omits Szechuan peppercorns, as it was illegal to import these peppercorns into the United States from 1960 to 2005. Western Kung Pao cuisine also commonly substitutes skinless, roasted, unsalted peanuts for the fresh nuts. Kung Pao dishes are considered a menu staple in many North American, Szechuan-style Chinese restaurants.