Combine salt and water in container that is large enough for chicken.
Ensure salt is dissolved and submerge chicken, breast side down, and place in refrigerator for 12 hours. Chicken should be completely submerged.
After 12 hours remove chicken from brine and allow to completely drain.
Place on rack and refrigerate for minimum of 1 day, or up to 2 days to dry chicken out and allow salt to further pernitrate the meat.
Remove chicken from refrigerator 1 hour before cooking to bring up to room temperature.
Bring butter to room temperature, and preheat oven to 450°F.
Utilizing spatula mix butter in boil to soften.
Insert finger under skin, at neck opening, and pull skin away from breast to create a pocket. Work skin all the way to tip of breast.
Using spatula put ½ of butter mixture on one side breast meat (between meat and skin) and ½ on the other side. Utilizing fingers “squeegee” butter so it is evenly distributed across the entire surface of the breast. Should form a even and smooth surface.
Using hands rub entire surface of chicken with cooking oil. Evenly distribute Mesquite Salt & Pepper Seasoning to outside of chicken.
Using cooking twine, truss bird.
Place bird on roasting rack and insert in oven so bird is in the middle of the oven.
Cook at 450°F for 15 minutes. Turn oven down to 400°F and continue cooking for 40 minutes to 1 hour or until internal temperature is 165°F.
Allow bird to rest for a minimum of 20 minutes or up to 45 minutes before carving.