I love the simple dish of steamed scallops with mung bean vermicelli, usually found in Cantonese restaurants that specialise in seafood. Often, though, they use far too much pre-minced garlic, which can have a metallic taste. This recipe is a slight variation on the dish and is almost as easy.
XO sauce is a Cantonese condiment that was named to evoke a sense of luxury. It contains expensive ingredients: primarily dried scallops (conpoy) along with dried shrimp and sometimes, dried Chinese ham. You can make your own, or buy it from Chinese supermarkets or high-end Chinese restaurants (which usually make their own).
To drain the XO sauce, scoop it into a small sieve set over a bowl and press on the solids. Do not throw away the flavourful oil after draining it – you will need a little to drizzle over the scallops, but the remainder can be poured back into the jar and spooned off when needed.
Put the mung bean vermicelli in a bowl and cover with hot water. Leave for 15 minutes to hydrate.
Open the scallops and remove the dark digestive parts, but leave the coral and other edible parts attached to the meat. Cut the muscle that attaches the scallop to the bottom shell. Blot the scallops with paper towels. Reserve the bottom shells.
Drain the mung bean vermicelli in a colander, then use kitchen scissors to cut the strands into manageable lengths. Divide the vermicelli between the bottom shells (you might not need all of it), then place the scallops on top, nestling them into the vermicelli so they are secure.
Use a pastry brush to lightly coat the scallops with fish sauce. Top each scallop with a small blob of XO sauce, then place them on a heatproof plate that will fit into the steamer. You will probably need to steam the scallops in batches.
Place a metal rack with low feet in the bottom of a wok (or use a tiered steamer) and pour in water to the depth of about 3cm (1¼in). Heat over a high flame until the water boils. Place the plate of scallops on the rack and cover with the lid, then turn the flame to medium. Steam for five minutes or until the scallops are barely cooked.
While the scallops are steaming, mince the spring onions.
When the scallops are cooked, drizzle a small amount of the XO oil over each one, then scatter with the spring onion pieces and serve immediately.