Cut the tomatoes in half, horizontally. Use a small spoon to gently hollow out the inside of the tomatoes, discarding the seeds and reserving the pulp and being careful not to puncture the outer shell. Chop the reserved pulp and put in a medium bowl. Add the parsley, bread crumbs, cheese, and pepper and mix gently to combine. Place the tomato halves in a buttered casserole dish, and fill with the bread crumb mixture. Drizzle the top of the tomatoes with olive oil. Bake until the tops are browned, about 20 minutes.