Using a sharp knife, carefully butterfly each chicken breast by slicing it horizontally, but not all the way through, creating a pocket.
In a mixing bowl, combine the cubed mozzarella, halved cherry tomatoes, chopped basil, 1 tablespoon of balsamic glaze, salt, pepper, and garlic powder. Mix until well combined.
Stuff each chicken breast pocket with the Caprese mixture, packing it in tightly. You can secure the openings with toothpicks if necessary.
Drizzle olive oil over the stuffed chicken breasts and season with salt, pepper, and dried oregano.
Heat a large oven-safe skillet over medium-high heat. Once hot, add the stuffed chicken breasts and sear for 3-4 minutes on each side until they are golden brown.
After searing, transfer the skillet to the preheated oven and bake for 20-25 minutes, or until the chicken is cooked through and reaches an internal temperature of 165°F (75°C).
Once cooked, remove the chicken from the oven and let it rest for 5 minutes. Drizzle with the remaining balsamic glaze before serving.
Notes
Serve on a bed of fresh arugula, garnished with extra basil leaves and drizzled with additional balsamic glaze.