Spring bamboo shoots (chun sun, 春笋) are one of the most eagerly anticipated seasonal ingredients in Jiangnan and Zhejiang cooking — appearing briefly in March-April, they signal the end of winter and the beginning of the most vibrant season of the Jiangnan kitchen. In Hangzhou and Zhejiang, whole industries and restaurant menus are organised around the arrival of fresh bamboo shoots. They are eaten in every form: fresh young shoots eaten raw with salt; briefly blanched and dressed with sesame oil; braised in master stock with pork belly; stir-fried with minced pork and douchi; and preserved in multiple ways (dried, fermented, pickled) for year-round use.
Preparing fresh bamboo shoots: The outer leaves of fresh bamboo shoots are removed. The white, cone-shaped interior is sliced. Fresh bamboo shoots contain oxalic acid and a small amount of hydrocyanic acid (prussic acid) — these must be neutralised by blanching the sliced shoots in a large volume of boiling water for 5-10 minutes (with the lid off — the acids are volatile and escape with the steam). Drain and refresh in cold water. The blanched shoots can now be used in any preparation. Classic preparations: Hong shao sun (红烧笋, red-braised bamboo shoots): Braised in the hongshao style with soy sauce, Shaoxing wine, and a small amount of sugar. The shoots absorb the braising liquid and become deeply savoury. You run sun (油焖笋, oil-stewed bamboo shoots): Stir-fried in a generous amount of oil with soy sauce and sugar until glossy and slightly caramelized.
Fuchsia Dunlop, Land of Fish and Rice (2016)