1 cup black urad dal (maati maah)
1/2 a small raw papaya chopped (optional; I did not have any but is a good and recommended addition)
1 fish head (I used Rohu)
2-3 tbsp grated ginger
1/2 tsp soda bi-carb (khar, although is used in more quantity, about 4 tbsp)
Salt to taste
A pinch of turmeric powder
3-4 green chillies
1 tbsp mustard oil plus a little more for topping
1 tsp panchphoran (equal quantity of mustard seeds, cumin seeds, fenugreeek, onion seeds, fennel seeds)
Wash and soak the daal overnight.
Smear a little salt and turmeric on the fish head and fry them in mustard oil till crispy and golden on all sides.
Scrub the soaked urad dal to get rid of the skin as much as possible. Pressure cook the daal with the papaya (if using) with plenty of ginger, a little turmeric, whole green chillies, and soda or khar till the dal is very soft and sludgy. The soda makes it cook fast. Don't allow more than 3-4 pressure cooker whistles on medium flame. Let it cool completely with the pressure releasing on its own.
Now heat about 1 tbsp oil and add the panchphoran. Let it splutter and then add the boiled daal. Bring it to a boil and add the fried fish head. With the back of the spoon, lightly crush the fish head and stir the daal. Reduce the daal a bit to get a thick sludgy consistency. Remove from heat and top it with some raw mustard oil. This addition of raw mustard oil is the star of this dish. If however you find it too pungent, you can heat a little mustard oil to smoky hot and then add it. Enjoy with hot steamed rice at the beginning of your meal.