Heat a pan and add oil to it

Add coconut and stir well

When its started becoming brown, add coriander seeds

Stir well and add curry leaves and shallots .

Mix it well and add red chilly flakes ,turmeric powder and chilly powder .

When its roasted well, off the flame

When its cooked add it in a blender

Grind it well

Heat a kadai and add oil to it

Then add onion ,ginger ,tomato, garlic and stir well.

When its brown

Add the grinded mixture to it

Add some water and black kokum to it and mix well

Add chilly powder to it ,if you need more spice.

When it boils add the fish to it

Close the kadai and keep in low flame.

Meanwhile heat a pan and add oil to it ,when it is hot add mustard and when it splutters add curry leaves and shallot to it .sauté it well and off the flame.

When the fish gets cooked well add the mustard mix to it

Then serve hot