What You need to prepare the gravy:
2 small onions roughly chopped
2 tbsp garlic cloves roughly chopped
few curry leaves
1 green chili roughly chopped
1/2 tsp of mustard seeds, fenugreek seeds and fennel seeds
Make a paste of mustard seeds, dry red chili, turmeric powder, add little water if required.
Start with heat coconut oil in a pan. I have used clay pot. You can use a normal non stick wok.
Once oil is hot, add mustard seeds and let it crackle. Add fenugreek and fennel seeds.
Next goes in the roughly chopped onions, garlic, curry leaves and green chilies .
Cook till everything turns nice and brown.
Add the paste you have prepared above. Also add the kokum extract.
Follow it up marinated fish. Add salt to taste, 1 to 2 cups of water depending on the gravy you need.
bring it to a boil and cook till fish is nicely cooked and a nice aroma comes out of the gravy.
That's it. All you need is to prepare some steam rice and salad. Your Rice and Fish curry is ready to enjoy.