1. Preheat oven to 450 degrees F.
2. Coat a baking dish with cooking spray.
3. Heat the oil in a large nonstick skillet over medium-high heat.
4. Add the onion and garlic; cook 4 minutes, or until softened.
5. Add tomatoes, olives and juice; cook 5 minutes.
6. Place fish in baking dish and top with tomato-orange mixture.
7. Bake 10 to 12 minutes, or until fish is no longer translucent.