It was on a trip back to his hometown, Chongqing, in Southwest China, that Yao Zhao first tasted green Sichuan pepper oil. His mother used it to enliven her cucumber salad. He was hooked, brought some back to Washington, D.C., where he lives, and used it in dishes he served to friends, to an enthusiastic reception. It has taken a couple of years, but now he is importing the green oil, which has an herbal and lemony profile, and the earthier red oil. Both convey the tingling, almost numbing sensation on the tongue that is the hallmark of Sichuan pepper. Use the green on salads, vegetables and seafood; add the red to meatier dishes, tofu and rich soups, taking baby steps as you add the oil. Mr. Zhao also said the red was not a ripe version of the green. They are two different varieties, made from a non-G.M.O. oil in the mustard family.
50 Hertz Red and Green Sichuan Pepper Oils, 3.4 ounces, $12.95 each, or $27.95 for both red and green in a gift box, 50hertzfoods.com.