About this recipe:I have been making this for maybe 15 years. It has been through a few tweaks here and there but I think it's pretty tasty now. Good at any time of year. I make it with salmon as the richness of the fish works well with mustard seeds and ginger, but you could try it with any fish that you like.
Mix the fish with the turmeric and 1 teaspoon salt, cover and put in the fridge for a couple of hours.
When you are about to start cooking the onions, remove the fish from the fridge and let it come to room temperature.
Take a large, flat pan and heat 2 tablespoons of the oil, adding the mustard seeds. When they are just starting to pop, add the chilli and bay leaf and cook for one minute.
Tip in the onions, turn down the heat to really low and cook for around half an hour. You want the onions to soften a little, but not burn.
For the last five minutes, add the ginger, the garlic, salt, chilli powder and sugar, and continue to cook very slowly.
Remove the onion mixture from the pan and transfer to a bowl, making sure you get all the bits in there.
Pour the remaining two tablespoons of oil into the pan and turn the heat up. When the oil is starting to do it's mirage thing, throw in the fish and let it brown slightly on its edges, around five minutes should do, turning the fish quite often.
Add the onion mixture, and the milk and yoghurt, and enough water to come half-way up the mixture (around 100ml should do).
Simmer for 10 to 15 minutes, then sprinkle on the garam masala and the coriander. The yoghurt may split and look a little odd, but it won't affect the taste. Serve hot with rice or parathas, and some salad.