Pat dry the chicken with a paper towel.
Gently lift the skin from around the neck opening and above the chicken breast and slide a teaspoon of herbed garlic butter under the skin above each chicken breast.
Mix the herbs, garlic, pepper, salt, and half lemon zest together to create your lemon herb rub. Alternatively you can use a store brought lemon herb dry rub.
Season the chicken generously with the seasoning. Be sure to rub the seasoning into all the grooves and spaces between the wings and legs of the chicken. Sprinkle the remainder of the lemon zest over the top of the chicken rub evenly across the chicken.
Cut the lemons into quarters and/or eighths. Start with the lemon that you have already zested. Use the lemon quarters to stuff the cavity of the chicken. Once the quarters are in there push in some of the eighths of lemon to ensure that it is a nice tight fit. Place two rosemary sprigs, cut to the size of the chicken. Wrap the chicken either in a container, foil tin or cling wrap and allow it to rest. When ready to cook preheat the smoker to 200°F with super smoke on.
Place the chicken directly on the grill. Insert the smoker/BBQ thermometer probe into the breast of the chicken, trying to position the probe in the thickest section of breast. Ensure the other end of your smoker/BBQ thermometer is connected to your Traeger (or thermometer and turned on).
Smoke your chicken for 60mins/1 hour.
After the 1 hour, increase the Traeger temperature to 350°F. Cook until the internal temperature reaches 140°F.
Once the internal temperature reaches 140°F, increase your Traeger temperature to 450°F until the internal temperature reaches 160°F.
Once cooked remove the chicken from the grill and wrap in foil for an hour.
Once cooled you can remove the lemon quarters from the cavity and carve the chicken.