Preheat the oven to 190C/375F/Gas 5. For the seasoning, mix all of the seasoning ingredients together in a bowl.
For the snapper, chop the onion, peppers and garlic. Arrange the vegetables in the base of an ovenproof dish.
Place the fish on top of the peppers and sprinkle with the seasoning.
Drizzle with sunflower oil and cook for 20-30 minutes until the fish is cooked all the way through. Serve at once.
