Use the nest with black fungus egg fried watercress bar, black fungus soaked well in advance. Good black fungus, soaked in cold water, need more than 8 hours. Time emergency can be soaked in warm water for two or three hours. Boil water in a pot. After boiling, drizzle some veggie oil. Blanch the watercress, then squeeze out the water and chop. Blanching with cooking oil, blanching color bright green. Beat the eggs and chop the black fungus. Drop a little rice vinegar into the egg mixture. Add oil to the pan, add the egg mixture and keep stirring. Do not break the egg. Stir-fry the eggs quickly to avoid any paste. Add the black fungus and stir fry well. Add the black fungus fire should not be too large, black fungus fried fly. Then add the cut watercress, add the right amount of salt, fish sauce and stir fry.