Fish fillets with orange sauce, mastiha and green olives

1 small Merlin orange
4 fresh tomatoes peeled seeded and finely chopped
2 tablespoons fresh orange juice
2 drops Chios mastiha oil or more to taste
⅓ cup finely chopped fresh scallion
2 tablespoons freshly squeezed lemon juice
2 tablespoons extra virgin olive oil
½ cup chopped green cracked olives pitted
1 teaspoon crushed coriander seeds
1 pinch red pepper flakes
½ teaspoon paprika
2 teaspoons fresh oregano or coriander
4 fillets of fresh cod 180 g each or other white fish fillets such as sole or perch
salt and freshly ground black pepper
2 teaspoons finely chopped lemon zest
2 teaspoons finely chopped orange zest
2 tablespoons extra virgin olive oil infused with Mastiha

Grate the orange and reserve the zest for the fish. Then peel the orange, removing all the white pith. Cut the orange into 0.5 cm cubes.
Mix the ingredients for the sauce in a bowl, cover it, and let it sit in the fridge for 1 hour. Take the bowl out of the fridge 15–20 minutes before serving the fish.
Preheat the oven to 190˚C. Lightly oil a glass baking dish large enough to hold the fish in a single layer. Season the fish with salt and pepper on both sides to taste. Place the fillets in the baking dish and sprinkle with the lemon and orange zest.
Drizzle with the Mastiha-infused olive oil. Bake the fish for about 12 minutes, until tender when pierced with a fork.
Transfer to a serving platter, top with the sauce and pan juices, and serve.