- Preheat the oven to 200°C/gas 6. Place the potatoes into a pan of boiling water for 7 minutes.
- Drain the potatoes and place in a line onto a large roasting dish (as a bed for fish) leaving a gap each side.
- Spread the tomatoes over the potatoes, then place the red and yellow peppers down either side of the potatoes and sprinkle with the garlic, chillies, oregano sprigs and olive oil, reserving 1 tbsp of the olive oil. Bake for 30 minutes, turning the dish half way through to ensure even cooking.
- Meanwhile, slash the fish 5–6 times down each side, rub the skin with the remaining olive oil and season with salt and black pepper. Place the fish on top of the potatoes.
- Return the dish to the oven and bake for a further 20–25 minutes (depending on the size of the fish), again turning the dish half way, until the fish is cooked through. Serve with the roasted vegetables.
- This recipe works well with other whole fish, such as trout or bream.
- It's brilliant with salmon steaks or any white fish steaks, especially for people who don't like fish bones. If using steaks or fillets rather than whole fish, increase the vegetables cooking time by 10 minutes and reduce the fish cooking time to 15 minutes, depending on the size of the fish.
- It makes a great dinner party dish.