Katla Kalia is a traditional Bengali fish curry made with katla fish, a popular freshwater fish in India. The curry is rich and flavorful, with a thick and spicy gravy. The fish is marinated in a mixture of spices and then cooked in a tomato-onion gravy with aromatic spices. It is typically served with steamed rice or roti. Katla Kalia is a popular dish in Bengali cuisine and is often prepared for special occasions and festivals.