Place the boneless chicken breasts in a glass or plastic container, or in a resealable food storage bag. In a separate bowl or large measuring cup, combine the balsamic vinegar, extra-virgin olive oil, minced garlic, kosher salt, dried oregano, dried basil, dried thyme, and freshly ground black pepper. Whisk these ingredients together until they are well combined.

Next, pour this marinade mixture over the chicken, ensuring each piece is thoroughly coated. Cover the container with a lid or seal the bag tightly, then place it in the refrigerator. Allow the chicken to marinate for a minimum of 1 hour and up to 6 hours for optimal flavor infusion.

When ready to cook, preheat your grill or grill pan. Place the marinated chicken on the grill, turning occasionally to ensure both sides are evenly browned and the chicken is thoroughly cooked. Cooking time will depend on the thickness of the chicken pieces; standard chicken breasts will need approximately 6 to 8 minutes per side, while thinner cutlets will require less time.

The chicken is done when it reaches an internal temperature of at least 165°F, measured at the thickest part using an instant-read thermometer. Once fully cooked, remove the chicken from the grill and let it rest briefly before serving. Enjoy your flavorful and juicy grilled chicken!