bean sprouts
Sprouted mung beans, often sold simply as bean sprouts, crisp, juicy and mild.
Fresh sprouts are sold in the chilled section of larger supermarkets and always at Asian grocers; they keep only a few days and should be white and firm, not brownish or slimy. Jarred sprouts are available everywhere but are soft and lack the crunch that usually matters.
Substitute:
Finely julienned napa cabbage stems or thinly sliced pointed cabbage give similar freshness and crunch, but taste more cabbagey and are less juicy.