Nasturtium officinale
This is another one which I never associated with Chinese cuisine until I came here. It seems the Chinese agree with me. The most common name is 西洋菜 (Mand: xī yáng cài; Cant: sai1 joeng4 coi3), which simply means "Western vegetable'.
What we are talking about is watercress. Despite the Latin name, this has no relationship to the flowers commonly referred to as nasturtiums.
Alternative Chinese names are 豆瓣菜 (Mand: dòu bàn cài; Cant: dau6 baan6*2) and 水田芥 (Mand: shuǐ tián jiè; Cant: seoi2 tin4 gaai3), the latter meaning 'paddy field mustard'.
In Cantonese, 西洋菜 (Mand: xī yáng cài; Cant: sai1 joeng4 coi3) is also slang for 'foreign girl or young woman '. The things you learn on eGullet!
It is mainly fried with garlic, like so many greens, or used in soups, particularly those made from pork bones. I have never seen it in salads or seen a bowl of green watercress soup like I know (and make).
However it also comes dried to add to soups, and even with all the ingredients you need except water is a 'soup mix' pack. I've never gone there.
Dried Watercress
Watercress soup mix
