Marinate the fish steaks with little turmeric powder and salt. Keep aside.

Powder yellow mustard seeds to yield the required amount for curry as per recipe.

Blend tomatoes, garlic, 3 green chilies, powdered mustard, salt and half cup of water to a smooth paste. Keep aside.

Heat mustard oil in a pan until smoking hot. Remove from heat for 30sec and then keep back

Add nigella seeds and let it sizzle for about 10 sec. Add the tomato-mustard-chilli paste.

Cook until the excess water is evaporated and oil is released. This would take about 10 mins.

Reduce heat and cook for anouther couple of minutes until it darkens a little

Add one and half cups of water, mix well and bring to a boil. Simmer for about ten minutes.

Pan fry the marinated fish steaks in mustard oil until golden brown.

Add the fish to the mustard sauce and cook for a couple of minutes more.

Garnish with coriander leaves and serve hot with steamed rice.