Before starting, you can open the can and open up the fish to remove the brittle bones. Keep the sauce for later.
Set the pan on the stove on low fire and add the oil in.
Once the oil is hot, add in the spices and when they start to crackle a little, add in the curry leaves followed by the sliced onions, garlic and red chillies. If you're using tomato instead of tamarind juice and can take a good heat, now is when you add the tomato and the dried chillies.
Increase the fire to medium and cook them for about 3-5 minutes until they start softening.
Add in the chili powder, mix everything around and let them all cook for about 2-3 minutes, add a pinch of salt and if you're adding tamarind juice, now is when you do that. (You can add a little bit of water if it starts drying up).
Stir in 5 tbsp of the canned sardine tomato sauce and let that cook for 1 minute before tasting it to make sure you are good with the heat and the salt. If it's not spicy enough, you can add 1 more tbsp of chili powder and if it's too spicy, you can add 1/2 more tbsp of the canned sardine tomato sauce. Then let that simmer for about 2-3 minutes.
Add in the fish, mix it up with everything in the pan and let it fry for about 2 minutes before smashing the fish into smaller chunks. Let it cook for about 5-6 minutes.
If there is too much gravy, then you can increase the heat and let it dry up a little. Once that's done, turn off the heat, add in the coriander and mix it up.
Fold it into a slice of bread or make a clamp toast sandwich, using a sandwich maker. Enjoy!
