01 - Preheat the oven to 400°F.
02 - Cut a pocket into the side of each chicken breast without cutting all the way through.
03 - Drizzle olive oil over chicken breasts and season both sides with salt, pepper, and Italian seasoning.
04 - Fill each breast with 2–3 slices of mozzarella, several tomato slices, and 4 basil leaves. Secure with toothpicks if necessary.
05 - Heat a large oven-safe skillet over medium-high heat and sear stuffed breasts for 2–3 minutes per side until golden.
06 - Transfer skillet to oven and bake for 18–22 minutes until chicken is cooked through and cheese is melted.
07 - Combine balsamic vinegar and honey in a small saucepan; simmer over medium heat, stirring occasionally until reduced by half and syrupy, about 8–10 minutes.
08 - Remove toothpicks from chicken and drizzle with balsamic glaze before serving.