Heat an oven-safe skillet over medium heat with the olive oil until the oil is shimmering.
Add the breasts to the pan and cook for 4 minutes, without moving them for a good sear. Then turn and sear the other side until they are golden brown.
Remove the pan from the heat, and add the cherry tomatoes, garlic, and Italian seasoning. Toss to combine.
Layer two pieces of mozzarella and two/three slices of Roma tomato on each piece of chicken (or as many as it takes to cover the chicken).
Transfer the oven-safe skillet to the oven and bake it for 8-10 minutes, or until the mozzarella is melted and the internal temperature of the meat registers 165°F.
Optional: crisp the tomato and mozzarella by broiling on high heat for 2-3 minutes or until your desired doneness.
Sprinkle over the basil leaves and drizzle on the balsamic glaze. Serve immediately.
Notes
Storage
Leftovers can be kept in an airtight container in the fridge for up to three days.