Marinate fish with ingredients mentioned under marination. Set aside till we need.
Fry onions in 1 tbsp oil until lightly golden. Saute tomatoes as well until soft and mushy.
Fry coconut, red chili powder, turmeric (optional) along with onions and tomatoes until the mixture turns fragrant. Make sure the raw smell has gone away from all the ingredients.
Cool this and blend to a smooth or coarse paste to suit your liking. If needed add 2 tbsp water to blend well.
This step is optional. Fry fish in 1 tsp oil slightly until the raw smell goes away just for 2 to 3 mins on both sides.
Add 1 tbsp more oil to the kadai. Allow cumin to splutter. Fry onions, curry leaves and green chili until the onions turn golden.
Saute ginger garlic until the raw smell goes off.
Add the ground paste, red chili powder (optional) and garam masala. Fry until the mixture smells good.
Pour 1 ¼ cup water. Bring it to a boil. Cook until the oil begins to separate and the gravy thickens a bit.
Drop the fish pieces and cook on a medium heat covered.
Gently flip them after 3 to 4 mins or more depending on the thickness of the piece.
Cook on both the sides until cooked. Fish pieces bulge a bit when cooked completely.
Garnish with coriander leaves if desired.
The kind of garam masala to use depends on ones choice of the gravy. Some folks do not prefer strong garam masala as they like to keep the fish flavour dominant. But we use a stronger garam masala. Also do adjust the quantity of masala to suit your taste.