Clean the prawns well and cook adding chili powder, turmeric powder, crushed ginger and garlic, pepper powder, tamarind and salt. Dry out the gravy completely and desiccate it. Beat the egg white well. Add maida, pepper powder, soya sauce, salt and water and mix it to the consistency of idli batter. Heat oil in a tawa and dip the prawns one by one in the batter and fry them.