1. Sprinkle tomatoes with salt and place, cut side down, on a paper towel–lined plate. Let stand 30 minutes to drain.
2. Preheat oven to 425ºF. Mist a baking dish with cooking spray, then arrange tomato halves, cut side up, in a single layer in dish.
3. In a small bowl, combine herbs, shallot and garlic. Add pepper, to taste. Spread herb mixture evenly over tomatoes. Drizzle with oil.
4. Bake in oven until cooked through, about 20 minutes. Remove dish from oven, top with fresh basil and serve.