Using a flat frying pan, heat 2 tbsp of
vegetable oil until very hot. Mix the flour and water into a thin
liquid and pour into pan. Allow to brown lightly. Crack the eggs into
the batter and spread round while whipping them lightly. Fry them
until brown on one side. Gradually add the rest of the vegetable oil
as the omelet is frying. When the omelet is cooked, shred it into
large pieces and add in the oysters. Add the fish sauce and chili.
Stir well. Garnish with coriander leaves and spring onions and serve.