Wash the fish nicely atleast for couple of times. Clean inside the belly with your fingers tips to remove extra dirt.
Once the fish is washed and cleaned nicely pat them dry with clean kitchen towel. Take the fish and make 2-3 deep incision on both side of the fish. It will help to penetrate and absorb the flavors of the masala nicely.
In a large platter or bowl add in the masala powders one by one, rice flour, ginger garlic paste, lemon juice and salt. Mix well to combine.
Then add 1-2 teaspoon of water and the curry leaves to the mixture. (Curry leaves gives an aromatic flavour to the fish). Mix well to form a smooth masala mixture.
Now take the fish and apply this mixture onto the fish and coat them well with the masala including the slashes and the stomach. Keep aside for 15 to 30 minutes atleast. (You can keep for longer duration in refrigerator).
Heat 1-2 tablespoon oil in a heavy cast iron skillet (tawa). Once the oil is hot, simmer it and fry green chillies. Remove and keep aside.
Now carefully place the mackerel in single layer over the hot tawa. I fried 3 mackerel in one batch.
Please note that the tawa and the oil should be hot. Otherwise the fish will stick to the tawa (skillet).
Fry them over medium flame for about 2-3 minutes. Flip over the fish and fry again for 2-3 minutes. Flip over and fry both sides until crisp and golden brown approximately for 1-2 minutes each on both the sides.
Remove them and keep aside. Repeat the same procedure with the remaining fish.
Serve the fried mackerel with fried green chillies, onion rings and lemon wedges.
Enjoy the delicious and tasty mackerel tawa fry with your meal or with your favourite drink.