Thaw fish, if frozen. Rinse fish; pat dry with paper towels. Sprinkle fish lightly with salt and pepper.
Preheat oven to 450 degrees F. In a large skillet heat olive oil over medium heat. Add the next four ingredients (through garlic); cook 7 to 9 minutes or until vegetables are tender and light brown. Remove from heat. Stir in wine, dill weed, and additional 1/4 teaspoon each salt and black pepper.
Reserve 1/4 cup of the vegetable mixture; spoon remaining vegetable mixture into a 2-quart square baking dish. Place fish on top of vegetables, tucking under any thin edges. Spoon reserved vegetable mixture over fish.
Bake, uncovered, about 12 minutes or until fish flaked easily. Transfer fish and vegetables to serving plates. If desired, top with additional snipped fresh dill weed.