Rub the fillets with garam masala, salt and pepper. Sear both sides in a frying pan in oil, chop into bite sized pieces and set aside
In a food processor add the tomatoes, garlic, cilantro, oregano, lemon juice, ginger, cream and curry powder. Process til smooth
Add the fish, onions and cauliflower and butter to a wok or large pot and cook til onions begin to turn transparent.
Add sauce to the pot, bring to a boil, then lower to a simmer and simmer for 20 minutes or so, stirring occasionally
Serve with basmati rice