De-head and clean the bombay duck carefully. Your fishmonger could as well do this for you if you were patient enough to wait :).
Heat oil in a pan, add the chopped garlic and fry on a medium flame till golden. Add the chopped onions and green chilies. Continue to cook till the onion starts to caramelize.
Add the bombay duck, turmeric powder, red chili powder and salt. Turn the heat to a high and stir occasionally. The bombay duck shall release plenty of water and break up, don't worry, keep stirring once in a while. Once the fish starts falling off the central bone, carefully remove the bones with a spoon.
Now reduce to a medium flame and continue to cook till this turns golden, slightly sticky in texture and starts releasing oil. Yes, it was this simple, we are done !!
Adjust the seasonings (maybe a couple of extra chilies to spike up the heat further) and add the chopped coriander leaves.and shoots. Serve hot with steamed rice.