Apply ginger-garlic paste, lemon juice, salt and egg white to the murrel pieces and marinate for about half an hour.
Take maida, corn flour and baking powder in a bowl, add water and prepare a batter.
Transfer the marinated murrel fish pieces into the batter.
Take a deep bottomed frying pan, add oil and heat. Carefully drop the murrel fish pieces one by one along with the batter into the boiling oil and deep fry on medium flame until the pieces turn deep brown.
Serve hot along with onion slices and vegetable salad.