Cut each side of the fish. Then put ½ teaspoon salt inside of the fish cut.
Heat oil in a pan, fry the fish until golden brown.
Heat 2 tablespoon of oil in another pan, saute onion, tomato, carrot, and ginger. Mix until softened.
Pour the water, ketchup, and sprinkle it with salt, ground black pepper.
Mix until the mixture boils.
Then, pour in the vinegar and add sugar.
Now, pour the diluted corn starch into the pan.
Then, carefully add the fish. Simmer for 2 minutes only.
Transfer onto a serving plate and top it with bell pepper and young onion.
Serve hot and enjoy!