Remove and discard the bones from the fermented fish. Dice the flesh and place in a mixing bowl with the pork, garlic, pepper and sugar. Mix together well, then stir in the whole beaten egg. Spoon the mixture into a 600ml glass or ceramic bowl. Sprinkle the shallots over the top, then cover the bowl with plastic wrap.
Half fill a steamer, wok or large saucepan with water and bring to a rapid boil over a high heat. Set the bowl in the steamer, then cover and steam over high heat for 30 minutes.
Remove the lid and plastic wrap. Pierce the surface of the terrine five times with a bamboo skewer, then pour the beaten egg yolks over the terrine. Steam for a further 5 minutes, or until the egg yolks are set.
Remove from the steamer and garnish with coriander and chilli. Serve warm, with steamed jasmine rice.