Preheat the oven to 450ºF. Add the tomatoes and olive oil to an ovenproof baking dish. Bake at 450ºF until the tomatoes release their liquid and little remains. Mix in remaining ingredients except balsamic and basil. Continue roasting until no liquid remains and the tomatoes are well browned in places. Stir in the balsamic and basil, season to taste with salt and pepper, then cool to room temperature before serving.