First, pour some salt and black pepper on the fish fillets and massage them by hand. Now put the fish fillets in the refrigerator for 15 to 30 minutes to taste.
Finely chop the coriander and fenugreek and set them aside. Now, chop the onion finely, then put a suitable pot on gentle heat.
Pour 2 tablespoons of oil into the pot, then add the chopped onion to the pot. Saute the onion for 5 minutes until completely soft, then add the turmeric.
Now saute the onion and turmeric for 2 minutes to combine. Meanwhile, finely chop the garlic and add it to the pot. Saute the garlic for 2 minutes, then add the chopped fenugreek and coriander to the pot.
Now add 1 to 2 tablespoons of oil to the pot and saute the vegetables for 15 to 25 minutes until they change color.
Meanwhile, pour the tamarind into a glass of boiling water. After 15 minutes, strain the tamarind with a sieve, then add it to the pot with 2 glasses of boiling water.
Allow the vegetables to cook for about 30 minutes. At this time, you can prepare the fish. Remove the fish from the refrigerator, place a large skillet over medium heat and add 4 tablespoons of oil.
Once the oil is hot, add the fish fillets to the pan and fry each side of the fillets for 5 minutes. Once the vegetables are cooked, add the fried fish to the pot and let them cook for another 20 to 30 minutes.
Finally, taste the food and add some salt and pepper if needed. Do not forget that this delicious dish should be served with Iranian rice.