Remove the skin of the fish and fillet on both sides. Wash and drain well.
Mix together all the ingredients: corn flour, ginger-garlic paste, red chilly powder, mustard paste, turmeric powder, lemon juice and required salt to a smooth paste.
Apply the paste on the fish fillets and marinate for fifteen minutes.
Add oil to a shallow frying pan and deep fry the marinated fish fillets to a golden brown color.
Serve cat fish(wallago/valuga) special recipe hot with onion and vegetables salad. Very good breakfast item.