For Vegetable Balls : Mix cabbage, cauliflower, carrot and french beans in a bowl and thoroughly rub in 1 tsp salt.
Add spring onion, capsicum, green chillies, black pepper powder, ginger & garlic paste, refined flour and cornflour. Mix thoroughly
Shape spoonfuls of the mixture into small balls. If you find it difficult to form balls, sprinkle a little water to bind the mixture.
Heat sufficient oil in a wok and deep-fry vegetable balls in small batches for 3-4 mins on medium heat or until golden brown.
Drain on absorbent paper and keep aside.
For Sauce : Heat the oil in a wok or frying pan on a high flame.
Add chopped onions and saute till it turns translucent.
Add ginger, garlic and green chillies and saute it for half a minute on high flame.
Add the vegetable stock, soy sauce, cornflour paste, sugar , black pepper powder, salt , sweet & sour sauce and simmer for a few mins or until the sauce starts to thicken, stirring continuously.
For Serving : Just before serving, put the vegetable balls in the sauce and bring to a boil. Garnish with spring onions and serve hot with noodles or boiled rice.