To Spatchcock the chicken, remove the backbone by cutting down both sides of the backbone.
Next turn the bird over and make a cut down the keel bone, which is right in the center. This will allow the chicken to lay flat.
When ready to cook, start the Traeger on smoke with the lid open until the fire is established (4 to 5 minutes). Set the temperature to 450 degrees F and preheat, lid closed, for 10 to 15 minutes.
White the grill is preheating, rub the chicken with the fennel, garlic, salt, and pepper, and let it come almost to room temperature (This will help it cook faster).
Place the chicken, skin-side down on the grill. Cook 8 to 10 minutes, or until there are good grill marks.
Turn the chicken over and cook until the meat reaches an internal temperature of 160 degrees. Enjoy!