Slice chicken breasts in half longways so you have 2 thinner pieces. Add to a large mixing bowl and pour one cup of balsamic vinaigrette into the bowl. Toss to coat chicken completely.

Cover the bowl and place in the refrigerator to marinate. Marinate the chicken for at least one hour, but up to 8 hours.

Remove marinated chicken from the fridge and preheat the grill or grill pan to medium high. Remove chicken from the marinade, but save the marinade on the side.

Place chicken on the hot grill. Grill on one side for 2 minutes then flip and baste the chicken with extra marinade. Grill for another 2 minutes. Flip and baste again and grill for 2 more minutes. Flip one final time and grill for 2 minutes. Close the grill between each flip.

The chicken will be on the grill for a total of 8 minutes or until the internal temperature reaches 165F. Allow the chicken to rest on a cutting board or plate for a few minutes before enjoying.