To make the burgers: Combine all the ingredients for the burgers, except the olive oil, and season with a little salt and black pepper. Shape into six burgers and set aside while you make the coleslaw.
To make the coleslaw: Place the cabbage, carrots, coriander, scallions and garlic in a large bowl. In a small bowl mix together the fish sauce, sweet chilli sauce, soy sauce, sesame oil, olive oil and lime zest and juice. Season with a little salt and black pepper. Pour the dressing over the vegetables and mix well to combine.
Heat the oil in a frying pan and cook the burgers for 4-5 minutes on each side.
Combine the yoghurt with coriander. Place a spoonful of coleslaw on the bottom half of each bun, spoon on a little of the yogurt mixture, then place the burger on top. Serve the remaining coleslaw and yogurt on the side.