bamboo shoots
Young, tender shoots of the bamboo plant, mild and crisp with a fibrous bite.
Caution: Fresh bamboo shoots contain cyanide-releasing compounds when raw and must be peeled and thoroughly boiled before eating.
Precooked bamboo shoots in cans or vacuum packs are found in the Asian aisle of many supermarkets, whole precooked shoots, as Japanese cooking prefers them, more often in Asian grocers, and fresh ones only rarely in spring. Rinse or briefly blanch preserved shoots before use to soften the tinned taste.
Substitute:
There is no true substitute; canned water chestnuts match the crunch but are sweeter and less fibrous.