Place the chicken breasts, ranch seasoning mix, and buffalo sauce in a large resealable bag.
Seal the bag and gently turn to coat the chicken evenly. Refrigerate and marinate for at least 1 hour.
Preheat the grill to high heat.
Remove the chicken from the marinade and discard the remaining marinade.
Grill the chicken over high heat for about 2 minutes. Flip, then reduce the heat to medium.
Continue grilling until the chicken reaches an internal temperature of 165°F, about 15–20 minutes depending on the thickness of the chicken breasts.
Remove from the grill and serve immediately.
Notes
Chicken thighs, drumsticks, wings, or pork chops can also be used, but cooking times will vary.For extra buffalo flavor, brush the cooked chicken with additional fresh buffalo sauce just before removing it from the grill. Do not use leftover marinade for basting.