Raaja Gobboru (Mackerel in Rustic gravy)

Mackerel is an oily type of coldwater fish that can be eaten canned or fresh. It is enjoyed by many people and known especially for its nutritional benefits, such as omega-3 fatty acids.
This Mackerel curry is a rustic village recipe which my great grandmother who lived in Kerala used to make. She used a traditional hand mortar to make the masala, and cooked it in earthern pot which made it even more tasty.
I have eaten and loved this during my childhood but somehow it was out of our memory from a long time.
During my recent visit to Mangalore/Kerala, I managed to ask my aunt, grand aunt and Mom and with their part of partial recipes I managed to recreate it, just the way my Great GrandMom would cook. 

Ingredients:
Mackerel - 4 - Cleaned and cut in pieces
Coconut fresh/desiccated - 1 handful
Roasted Dry Red chillies - 8-10 depending on the palate
Roasted Coriander seeds - 1 tsp
Roasted Methi/Fenugreeek seeds - 1 tsp
Tamarind - 1 small lemon sized ball
Ginger - 1 inch piece
Garlic - 2 cloves
Green chilli - 1
Onion - 1 small
Oil - 1 tsp for garnishing (Optional - to get authentic taste)
Method:
Grind the coconut, roasted dry red chillies, coriander seeds, methi seeds and tamarind along with 1 cup water, to an almost paste ie till 3/4 smooth. Now add the raw ginger, garlic, onion and green chilli and blend for just 5 seconds, so that these raw ingredients remain coarse in the rest of the smooth paste.
Now take a heavy bottomed pan, keep on medium heat, put the ground paste in the pan, add the mackerel pieces, salt and mix well. Bring to boil. Garnish with 1 tsp of coconut oil for authentic taste. Serve hot with steaming boiled red rice or white rice.