- Clean fish properly and set aside.
- Grind together both kind of mustard finely and make paste with 1 table spoon of water and set aside.
- Take a pan which is specious enough to spread the fish in one layer. Heat oil in the pan in a medium heat.
- When oil is hot enough put the chopped onion to it and fry until it become soft.
- Then add Ginger paste, garlic paste, green chili paste, turmeric powder, cumin powder, salt and little bit of water; and stir it.
- Stir until oil separate from the masala, then add mustard paste and mix for 20 seconds. Don't mix it too much after putting mustard otherwise the curry become bitter in taste.
- Then put the fish and coat the fish with masala carefully. Add 1/2 cup of water and whole green chili; and cover the pan with a lid which don't have any hole (if there is whole in the lid you can put a piece of paper to close it) and wait 6/7 minutes, then flip the fish to opposite side, cover the pan and wait another 6 minutes.
- Then spread the coriander leaves, cover it and wait another 2/3 minute, then turn off the stove. Do not open the lid for 15 minutes.
- After that serve your delicious dish with hot rice.