01 - Preheat the oven to 400°F.
02 - Pat chicken breasts dry. Cut a deep pocket lengthwise into each breast without slicing through completely.
03 - Season both sides and inside the pockets of the chicken with salt, pepper, and garlic powder.
04 - Fill each breast with slices of mozzarella, tomato, and 4 basil leaves. Secure with toothpicks if necessary.
05 - Heat olive oil in an oven-safe skillet over medium-high heat and sear the stuffed breasts for 2 to 3 minutes per side until golden brown.
06 - Transfer the skillet to the oven and bake for 18 to 22 minutes or until the internal temperature reaches 165°F.
07 - Combine balsamic vinegar and honey in a small saucepan. Bring to a boil, reduce to a simmer, and cook for 5 to 7 minutes until thickened.
08 - Remove chicken from the oven, let rest for 5 minutes, then remove toothpicks. Drizzle with balsamic glaze and garnish with basil leaves and olive oil as desired.