Preheat oven to 425°F. In a large baking dish, combine cherry tomatoes, olive oil, minced garlic, oregano, salt, black pepper, and red pepper flakes. Toss to coat evenly.
Roast tomato mixture for 15 minutes until tomatoes are bursting and beginning to caramelize.
Remove baking dish from oven and add the rotisserie chicken chunks, nestling them among the tomatoes. Drizzle with balsamic vinegar.
Return to oven and roast for an additional 8-10 minutes until chicken is heated through and edges are slightly crispy.
Remove from oven and tear fresh basil leaves over the top. Sprinkle with mozzarella cheese and let sit for 2-3 minutes until cheese melts.
Serve hot with crusty bread, over pasta, or alongside your favorite grain.