Cut the fish into thick slices. Apply lemon juice and salt. Keep aside.
Make a paste of coriander, chilies, garlic, mint and cumin seeds.
In a bowl, mix curd, green paste, crushed fried onions, cut tomatoes, salt and all the above masalas.
Marinate the fish in it for 2 - 3 hours.
Soak the rice for ½ hour.
In a wide bottomed vessel, add 4 - 5 serving spoons of oil. Toss in the whole garam masalas.
Add in the rice and salt. Sauté for a few minutes and par-cook the rice in coconut milk.
Gently remove half the quantity of the semi cooked rice.
Layer the marinated fish over the rice in the vessel and sprinkle a little water if needed.
Heat the piece of coal over the gas flame until it turns red. Place it in a small bowl over the marination.
Now pour 1 tbsp. ghee over the coal, it will let out smoke. Cover the vessel with a lid and leave for a few minutes.
Remove the bowl and layer the remaining rice over it completely covering the marinated fish.
Now cover the vessel with a lid and seal the edges with foil.
Heat a tawa and place the vessel on top and cook on a very low flame for ½ an hour or until done.