Preheat oven to 400 degrees.
Lightly spray a shallow baking dish with cooking spray (olive or canola).
In a bowl, stir together oil, thyme, diced tomatoes, sliced olives, parsley, basil, chopped onions and lemon juice.
In the prepared baking dish, arrange the fillets skin side down and lightly season with salt.
Spoon the tomato mixture over the fillets
Bake, uncovered, in the middle of the oven for about 15 or 20 minutes or until fish just flake.
Garnish fish with lemon slices and fresh Thyme .