Start by breaking the elephant wood apple fruit with a rolling pin and scoop out the pulp from inside. Collect the pulp in a bowl.
Now, smash the pulp with a spoon and soak it in water for 10 minutes. After that, strain the pulp using a strainer.
Take a strainer and a clean bowl. Smash the soaked wood apple pulp with a spoon and strain it through a strainer. This will help you extract the fresh juice of the wood apple without any seeds or fibers.
Marinate the Hilsa fish pieces with turmeric powder and salt. Add ½ tbsp salt and a little less than ½ tbsp turmeric powder. Mix well and set it aside for 5 minutes.
Heat a wok and add 4 tbsp mustard oil to it. Let the oil become hot.
Once the oil is hot, add the Hilsa fish pieces. Fry them lightly, making sure not to overcook.
Fry both sides of the fish pieces by flipping them.
Take out the fried Hilsa fish pieces and place them on a plate.
Add the whole spices, black mustard seeds, and dried red chili to the same oil. Sauté them lightly, keeping the flame low.
Add turmeric powder and a little bit of water to the oil. Sauté it lightly.
When it starts simmering, add Kashmiri red chili powder to enhance the color. Sauté it for few seconds.
Once the raw smell of turmeric powder disappears, add the sour wood apple pulp juice. Mix all the ingredients well.Expert tips: This dish can be prepared with either tamarind or wood apple. Add water to achieve your preferred gravy consistency. I have added a total of 1 and ½ cups here.
Add ½ tbsp salt and let it boil.
When the gravy starts to boil, add the fried Hilsa fish pieces. Cover the wok with a lid and keep the flame medium to high.
After some time, open the lid. The dish is almost ready.
Add sugar and a little more salt. Flip the fish pieces to ensure both sides are cooked equally. Increase the heat on the gas stove.
The preparation is now ready. Turn off the flame and transfer Ilish Macher Tok to a serving bowl. Serve it with steamed Basmati rice or Bengali pulao.