Green mussels are marine bivalve in the genus Perna of the family Mytilidae. Thre are two green mussel species: Perna viridis (a.k.a Asian green mussell) and Perna canaliculus (a.k.a greenshell mussel or New Zealand mussel). In Vietnam, green mussels are harvested and modestly cultured in some coastal provinces like Nghệ An, Hà Tĩnh, Huế and Kiên Giang. Vietnamese chefs cook green mussels in a way that is similar to other Mytilidae mussels or bivalve mussels in general. Some common dishes: green mussel and star fruit soup, bánh khọt pancake with green mussels, stir-fried green mussels with lemongrass and chilli, grilled green mussels with cheese, grilled green mussels with spring onion oil, green mussel porridge…
Spring onion oil sauce is traditionally made with chopped spring onion (aka green onion or Welsh onion) in hot melted lard, however modern home cooks often use cooking oil instead, for convenience. Spring onion oil sauce is commonly added to grilled meat (pork chops for example), but also applied to sea shells including snails, oysters, scallops, cockles, or mussels.