In these days of global cuisine, when many seasonal fruits and vegetables are sold year-round because they're grown in so many parts of the world, it's refreshing to know some foods are available only at specific times of the year. Yes, you can occasionally find small green pea shoots (dau miu) in upmarket grocery stores (where they're usually sold as part of expensive mesclun mixes) but the right time (at least in Hong Kong) for this vegetable is from now until early February. In truth, the pea-shoot season is actually a little longer - from late October to early March - but at the beginning of the season, the shoots taste too 'green'; too late and they will be tough.
The best dau miu are the tips of the pea-shoot vine: look for the smallest leaves and shortest stems and tendrils - they're more expensive, but taste sweeter and are more tender. The leaves should be bright and fresh, not yellowing and wilted.
Dau miu doesn't weigh much, but, like spinach, it shrinks as it cooks. It tastes best cooked in a good amount of fat (preferably rendered chicken fat), which rounds out the flavour and gives the vegetable a silken texture. If stir-frying the pea shoots, let them wilt in the hot fat, then add a clove of garlic, a slice of ginger, a little salt and a splash of chicken broth, then cook for two to three minutes until tender.
The most luxurious pea-shoot dishes are made by Shanghainese chefs, who stuff the vegetable into delicate dumplings or cook it with the roe of hairy crabs (which also happen to be in season at the moment).