Wet-market vegetable vendors are selling huge piles of watercress. The vegetable is popular at this time of the year because it's considered 'cooling'.
What is it? A vegetable with a long stalk, small green leaves and a peppery taste. It's usually grown in water, hence its name.
What to look for: stems with lots of leaves; don't buy 'leggy' stems. Avoid watercress that is yellowing or flowering, which are indications the vegetable is old and the flavour will be bitter.
How to store: wrapped in a bag in the fridge. Use it within a few days of purchase.
How to use: the most popular Chinese way of eating it is in soup. Marinate sliced pork in soy sauce, rice wine, sugar, salt, white pepper and cornstarch. Heat a couple of tablespoons of oil in a pot, add sliced ginger and cook until fragrant. Add water (or a light chicken stock) and bring to a full boil. Stir in the watercress, lower heat and simmer for about 10 minutes. Add the sliced pork and simmer until cooked. Ladle into bowls and add a little white pepper and sesame oil.
For a western soup, saute some chopped leek or onion in butter. Add cubed potato, salt and pepper and chicken stock or water to cover. Bring to the boil then lower the heat and simmer until the potato
