Take flour, corn starch, vegetables,salt pepper, soda bicarbonate,ginger- chilli paste, soy sauce and mix well. Add two tablespoons of water. Make balls out of and deep fry them until golden and crisp.
Take oil in pan, saute the onions and green bell peppers. Add ginger, garlic and chillies. Mix well. Add soy sauce. Dissolve 2 teaspoon corn starch in 1 tablespoon of water. Mix the cornstarch mixture to the pan. Add in the sugar, salt and black pepper and the 1 cup of water. Mix well. Let it simmer for sometime and add in half of the scallions.
Once the sauce thickens, add the fried manchurian balls to the sauce. Garnish it with remaining half of the scallions.