Marinate the fish heads with salt and turmeric powder. Set them aside for 10 minutes.
Fire up the earthen stove. Place a deep-frying pan (kadai) on the stove.
Pour mustard oil into the kadai.
Add the fish heads to the hot oil.
After one side is done, flip them upside down.
Take them out onto a bowl.
Add potatoes to the oil. Sauté them with salt and turmeric powder. Once lightly fried, take them out.
Add cumin seeds, bay leaves, and red chilis.
Add chopped onions. Once the onions turn light brown, add tomatoes and a little bit of salt.
When the tomatoes cooked, add the onion-ginger-garlic paste. Mix well and sauté for a few minutes or until it thickens.
Add turmeric powder, red chili powder, Kashmiri red chili powder, coriander powder, and cumin powder. Keep stirring so that the spices mix well with the paste. Add a little bit of water.
Once the spices start releasing oil, add the lightly fried potatoes and sauté for a few minutes.
Add the half-boiled shredded cabbage and mix everything well.
Add a small amount of water and some salt.
Add the fried fish head pieces. Cover the pan with a lid and allow it to cook for 10 minutes.
Remove the lid and add roasted cumin powder. Mix well.
Meanwhile, the water will evaporate, and a thick texture will form.
Badhakopi Diye Macher Matha is ready. Pour it into a bowl and Serve it with steamed rice.