Preheat oven to 200ºC (400ºF). Heat the oil in a large non-stick frying pan over high heat. Add the mushrooms, garlic, salt and pepper and cook for 2–3 minutes or until golden. Top the bread with the mushrooms, mozzarella, buffalo mozzarella and oregano. Drizzle with oil and sprinkle with salt and pepper. Bake for 10–12 minutes or until golden. Slice into wedges to serve. Serves 4–6.