Ilish bhapa

Method

1. 1 Soak mustard seeds for 30 minutes, then blend them with green chilies and a little water to form a yellow paste.
2. 2 Mix mustard paste with yogurt, turmeric, mustard oil, salt, and a pinch of sugar.
3. 3 The sugar here isn't for sweetening, but to cut through the pungent bitterness of the ground mustard.
4. 4 Marinate the fish fillets in the sauce for 20 minutes, then lightly heat the banana leaves to make them pliable.
5. 5 Wrap the fish and all the sauce in banana leaves to form a tight package and tie it with string.
6. 6 Steam the wrapped fish for 18 minutes; steam in a tightly sealed package to prevent the mustard oil from evaporating and to ensure the fish cooks through with the sauce.

With an appliance

• Microwave 38 min

  Replace step 6: place the banana leaf-wrapped fish package on a plate and microwave at 700 W for 8 minutes, resting for 2 minutes before opening to retain the mustard oil aroma; steps 1–5 remain the same.