Slice the tomatoes from core to core. Remove and discard the seeds and juice, and add the tomatoes to a casserole dish. Drizzle with olive oil and sprinkle with salt and pepper.
Combine the 2 tablespoons olive oil, panko, Parmesan, parsley, garlic, shallots, red pepper flakes and some salt and pepper together in a small bowl. Fill the tomatoes with the panko mixture. Bake 20 minutes. Drizzle with a splash of olive oil before serving.