Spicy Buckwheat Noodles (Suan La Jiao Mian)

I adapted this spicy Szechuanese dish from Fuchsia Dunlop's cookbook Every Grain of Rice. It makes for a great side or appetizer dish as it can be served hot or at room temperature. The chicken is optional, but if you happen to have some left-over rotisserie chicken on hand, it would be a great addition. Prior to coming across this recipe, I didn't even know that buckwheat noodles were utilized in Chinese cuisine since I've only eaten them in Japanese restaurants as cold Soba noodles with julienned nori, sliced scallions, and a soy-wasabi-mirin-sake-sugar dipping sauce. Anyways, incredibly easy to make and really yummy.