The barramundi (Lates calcarifer) or Asian sea bass is of commercial importance and it is raised in aquaculture in Vietnam. One unique cooking style for this fish in Vietnam is raw fish salad or gỏi cá. In this dish, fish fillets are cured in a solution of citric acid from lime juice for long hours. Then, the fish fillets are mixed with vegetables and sauce just like other Vietnamese salad.
Raw fish salad is a Vietnamese century-old dish utilizing fresh fish fillets of various types. But this barramundi version is actually invented by a restaurant in Saigon more than 30 years ago following an accident. The restaurant owner accidentally dropped some fish fillets into a lime juice bowl which was intended to be used for another dish. This recipe article is just a reverse-engineered one based on the real dish.
Barramundi fish is the original ingredient, but corbia is a close substitution. The vegetable used in this dish spring onions or scallions. The sauce is said to be a mixture of mustard or mustard greens and chili sauce, but the detailed ingredients are the restaurant’s unrevealed secrets.
In a salad bowl, add the fish pieces and pour the lime juice, with ginger strips and some sesame oil. Submerge the fish for 2-3 hours (at least one hour).
In the mean time, soak the shredded scallions in a vinegar-sugar solution.
In a saucepan, add 3 tablespoons of fish sauce, 2 tablespoons of sugar and stir until the sugar dissolves. Turn off the heat and let the sauce cool off a bit. Add 2 tablespoons of lime juice and 1 tablespoon of yellow mustard then mix well.
In a salad bowl, add drained fish pieces and shredded scallions. Pour the salad sauce into the bowl and mix well.
If you're worried about raw fish dishes (tartare, ceviche, sushi or Vietnamese gỏi cá), freeze the fish fillets at -4°F/-20°C for at least 7 days. Alternately, freeze at a temperature of -31°F/-35°C and stored at this temperature or below for a minimum of 15 hours.