Cut slits crosswise across the chicken breasts, making sure that you don't cut all the way through.
Put all the marinade ingredients in a large sealable plastic bag and shake to mix. Then place the chicken breasts into the bag with the marinade. Marinade the chicken in the marinade from 1-24 hours in the fridge. Occasionally massage the chicken in the bag to ensure it is well marinated.
Either heat the grill or your barbecue and grill the chicken breasts on both sides for 8-10 minutes on each side or until cooked through.