To make the accras de morue:
In a large bowl let the salt cod soak in enough cold water to cover it by 3 inches, changing the water several times, for an least 8 hours or overnight. Drain the salt cod well in a sieve and in a food processor puree it. Add the flour, the milk, the egg, the baking powder, the allspice, and the garlic and blend the mixture well. Transfer the mixture to a bowl and stir in the chili, the scallions, and the coriander. In a deep fryer or large deep skillet heat 1 1/2 inches of the oil to 360F. on a deep-fat thermometer and in it fry teaspoons of the mixture in batches, stirring and turning them occasionally, for 1 to 2 minutes, or until they are golden and cooked through. Transfer the fritters as they are fried with a slotted spoon to paper towels to drain. The fritters may be made 2 days in advance and kept covered and chilled. Reheat the fritters on a rack in a shallow roasting pan in a preheated 450F. oven for 5 minutes. Serve the fritters with the sauce.
To make the sauce chien:
In a heatproof bowl combine the onion, the scallions, the bell pepper, the garlic, the chili, the salt, and the thyme. In a small saucepan bring the water to a boil with the vinegar, pour the vinegar mixture over the vegetable mixture, and let the mixture cool. Stir in the lime juice and the oil. The sauce may be made 2 days in advance and kept covered and chilled. Let the sauce come to room temperature, stir in the chopped coriander, and garnish the sauce with the coriander sprigs. Makes about 2 cups.