Glass noodles (or glass vermicelli) goes by many names, including fen si, bean thread vermicelli and cellophane noodles. It is made from mung bean starch, has a slippery texture and absorbs the flavours of whatever ingredients it's cooked with.
Yellow bean sauce, also called fermented yellow bean sauce, crushed yellow bean sauce or salted yellow bean sauce, is a Thai or Chinese ingredient that can be found in jars or bottles. Fresh green peppercorns are sold at shops specialising in Thai produce, which should also stock the holy basil.
I buy whole shrimp, cut off the heads and use them for the shrimp stock.
This dish is best cooked in a Chinese clay pot (also called a sand pot), but if you don't have one, use a cast iron pot, either plain or enamelled.
Make the shrimp stock. Cut off the heads from the shrimp and put them in a pan with 300ml (1¼ cups) of water. Place over a medium flame and bring to the boil. Lower the heat and simmer, with the pan partially covered with the lid, for about 20 minutes. Pour the ingredients through a colander placed over a bowl to catch the liquid. Press on the solids to extract as much liquid as possible, then discard the shrimp heads.
While the shrimp stock is simmering, prepare the other ingredients. Put the glass noodles in a bowl, add cool water to cover and leave to soak until fully hydrated. Pour into a colander to drain off the water.
Cut the shrimp down their backs through the shells and remove the vein (if it has one).
Cut the pork into thin, short strips. Thinly slice the onion and garlic. Cut the spring onions into 2.5cm (1 in) lengths.
Mix the yellow bean sauce with the soy sauce, rice wine, fish sauce and sugar.
From two of the peppercorn stalks, pull off the green peppercorns, then discard the stalk. Leave the other last one intact.
Pour the oil into a medium-size clay pot placed over a medium flame. When the oil is hot, add the whole stalk of green peppercorns and cook until the peppercorns start to darken and become fragrant. Turn the stalk over in the hot oil so the peppercorns are evenly cooked.
Add the onion and garlic and stir until the onion starts to soften.
Add the pork and individual green peppercorns and stir until the meat loses its pink colour.
Put the glass noodles in the pot (it will seem like too much, but it shrinks as it cooks), then pour in the yellow bean/soy sauce mixture. Immediately stir to coat the noodles with the sauce ingredients.
Pour in 225ml (1 cup) of the shrimp stock and the shrimp and mix thoroughly. Bring to the boil then lower the flame, cover the pot with the lid and simmer, stirring occasionally, until all the liquid has been absorbed and the shrimp are cooked, about three to five minutes. If it seems dry, or the noodles are scorching, add a little more shrimp stock, as necessary.
Stir in the holy basil leaves and the spring onion then garnish with whole stalk of green peppercorns before serving.