Preheat broiler to medium high.
Cut plum tomatoes in 1/2 lengthwise. Squeeze or scoop out most of the pulp and seeds. Place the tomatoes flesh side up in a heat safe dish and season them with salt and pepper. In a bowl combine the bread crumbs, Parmigiano, thyme, garlic and olive oil. Season mixture with pepper and sprinkle over the tomatoes. Place tomatoes under the broiler for 5 minutes or until golden brown