Lower the heat to medium. Allow the fish fried oil to cool down a bit otherwise the onion paste will burn and become bitter. This is very important.
Add the mustard seeds and the curry leaves in the hot oil. Sizzle them for a few seconds or until the mustard begins to pop.
Gently release the onion paste and sauté it for about 1 min.
Next, add the ginger garlic paste. Mix well with the onion paste and fry them well until the raw aroma completely disappears and you see streaks of oil oozing out.
Now, add the tomato puree. Stir well to mix. At this stage the masala paste in the pan will begin to bubble.
Throw in all the dry spices. Mix well and fry everything very well until oil begins to leave the sides of the pan. You'll get a lovely aroma at this stage.
Add the tomato paste and mix well. Fry everyhting for about 1 min.
Reduce the heat and pour the coconut milk. Mix it vigorously with the rest of the ingredients until a smooth and silky lump free consistency is reached. Move the spatula briskly in clockwise direction to mix the coconut milk. Fry for 2-3 mins until you see streaks of oil appearing.
Next, add 1 cup water. Give everything a very good mix. Cover and simmer the fish curry sauce on medium low heat. 5 mins is all you need. You will see oil floating at the top and the color of the curry sauce slightly changing and becoming darker and more lovely.
It's time to add the shallow fried Monkfish fillets to the curry sauce. Add the fillets, coat them well with the sauce. Cover and simmer until the fish is completely cooked through. It took me another 3 mins approximately.
Adjust the consistency of the fish curry sauce. Add more water if you prefer a thin sauce perfect for rice or reduce the water quantity and keep the suace a little thicker perfect to enjoy some cursty bread. Choice is yours enjoy!