Marinate the Chicken: In a bowl, whisk together balsamic vinegar, olive oil, salt, and pepper. Add the chicken breasts and marinate for at least 20 minutes (or up to 2 hours in the refrigerator for more flavor).
Cook the Chicken: Preheat a grill or stovetop pan over medium-high heat. Remove the chicken from the marinade and grill for about 6-7 minutes on each side, or until cooked through (internal temperature of 165°F). Let it rest for 5 minutes before slicing.
Prepare the Salad: In a large mixing bowl, combine the cherry tomatoes, diced avocado, mozzarella balls, and torn basil leaves.
Make the Dressing: In a small bowl, whisk together the remaining balsamic vinegar, olive oil, honey (if using), and a pinch of salt and pepper.
Assemble the Salad: Slice the grilled chicken and add it to the bowl of salad ingredients. Drizzle the dressing over the salad and gently toss to combine until everything is well coated.
Serve: Plate the salad onto individual serving bowls or a large serving platter, garnishing with extra basil leaves if desired.
Notes
Marinating the chicken for longer enhances the flavor.