Carefully slice a pocket into each chicken breast, making sure not to cut all the way through.
In a mixing bowl, combine the diced mozzarella, halved cherry tomatoes, chopped basil, balsamic glaze, salt, pepper, garlic powder, and dried Italian herbs. Mix well until all ingredients are evenly coated.
Stuff each chicken breast pocket with the mozzarella and tomato mixture, dividing it evenly among all four breasts. Secure the opening with toothpicks if necessary.
In a large oven-safe skillet, heat the olive oil over medium-high heat. Once hot, season the chicken breasts with salt, pepper, and garlic powder.
Sear the chicken breasts for 3-4 minutes on each side until golden brown.
Transfer the skillet to the preheated oven and bake for an additional 20-25 minutes, or until the chicken is cooked through and reaches an internal temperature of 165°F (75°C).
Remove the skillet from the oven and allow the chicken to rest for 5 minutes before slicing.
Garnish with extra fresh basil and a drizzle of balsamic glaze before serving.
Notes
Allow the chicken to rest before slicing for better juiciness.