Mix together soy sauce, vinegar and sugar until the sugar dissolves; taste and adjust to perfection.
Make a few cuts on the fish and stuff with ginger strips. Use 1-2 tbsp of mixture to marinate the fish for 15-20 mins (optional).
Heat the remaining sauce in a large iron cast skillet until it starts to bubble.
Arrange slices of daikon in the bottom and place the fish over them. Add the remaining strips of ginger, cover and simmer on lowest heat for 15-20 minutes (depending on the size of the fish).
Fillet the cooked fish using a flat turner or spatula and serve sprinkled with fresh scallions and coriander leaves.