Cut the grouper filets into smaller pieces (about 2 ounces each) and set aside.
Set a small pan over medium heat and dry-roast the spices for about 2 to 3 minutes, until aromatic. Grind the toasted spices in a coffee grinder. (Powdered spices may be substituted, but don’t roast them.)
Heat the oil in a pot over medium heat. Add the chopped onions and sauté until golden brown.
Blend the ginger and garlic with the cup of water, and add the paste to the onions. Sauté for 2 to 3 minutes over medium heat, until the raw flavor is gone.
Add the chopped tomatoes along with the turmeric powder and cook until the tomatoes are softened, about 6 to 8 minutes.
Add the curry leaves along with the coconut milk and bring to a boil. Lower the curry to a simmer and cook for 5 minutes. Add the roasted or powdered spices, and then the fish. Cook until the fish is cooked through, about 10 minutes.
Season with salt and garnish with cilantro.
Read more: http://www.livestrong.com/recipes/lillies-kerala-fish-curry/#ixzz2vmWmOfKQ