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