Preheat oven to 200°C. Place fish in a roasting pan. Cover with orange and lemon slices. Combine marinade ingredients and pour over the fish. Bake in oven for about 20-25 minutes.
Other things to try:
Go Oriental with soy sauce, chilli, garlic, ginger, orange juice and fresh coriander.
Rub the fish with Moroccan chermoula or harissa paste, squeeze over fresh lemon juice and roast. Serve scattered with fresh coriander.