Combine the fish sauce, rice vinegar, sugar
and 1/2 cup of water in a saucepan
and place over medium heat. Stir well and cook until just before boiling point is reached, then remove from the heat and allow to cool. To serve, add the garlic and chilli, then stir in the lime juice. Store tightly sealed in a jar in the fridge, for up to 5 days.
Yield: about 1 cup