In a bowl, whisk together the balsamic vinegar, honey, oil, garlic, Italian seasoning, and Dijon mustard. Season with salt and pepper to taste. Set aside.

In a separate bowl, toss together the tomatoes, mozzarella, and basil. Season with salt and pepper to taste. Set aside.

Preheat oven to 400 degrees F.

Heat the avocado oil in a large oven-safe skillet over medium-high heat. Season chicken with salt and pepper.

Add the chicken to the skillet in a single layer. Cook for 1-2 minutes on each side or until lightly golden brown.

Add the balsamic sauce mixture to the skillet and bring to a simmer, scraping up any brown bits from the bottom of the pan.

Immediately remove the pan from heat and add the tomato mozzarella mixture over the chicken.

Bake uncovered for 18-23 minutes or until chicken is fully cooked through, with an internal temperature of 165F.

Remove from the oven and rest for 5 minutes before serving.