Add oil to a heavy bottomed wide pan. When heated, add mustard seeds, cumin seeds when splutters, add fenugreek seeds and red chilies.
Now add the finely chopped onions and sauté a minute.
Add ginger garlic paste and green chilies and cook until the raw smell goes off.
Cook until onions are translucent.
Now add finely chopped tomatoes or puree. Here I am using finely chopped tomatoes.
Cover and took until the tomatoes are mushy.
Add turmeric, red chili powder, coriander powder, cumin powder and salt.
Mix well and cook for a minute or two.
Its the time to add our most important ingredient for pulusu is tamarind juice. Mix well.
Cover and cook on a medium low flame until the oil oozes out.
Add the fish pieces one by one and arrange them so that they are nicely dipped in the pulusu.
Carefully mix the pulusu and cook them for 3-4 mins. Do not over mix as the fish pieces will breakoff.
Sprinkle the chopped coriander leaves and switch off the flame.
Serve hot with white rice.