Rinse inside of chicken thoroughly. Salt chicken in and out with about 1 teaspoon of salt. Wrap in plastic and refrigerate for three days. If you don’t have the three days as a option, you can still make this chicken salting for one day.
When ready to roast, take chicken down to room temperature.
Preheat oven to 450 and place cast iron pan in oven at least 20 minutes prior to using. Rinse chicken, pat dry and season with salt and pepper.
Cut orange into quarters and stuff in bird. Place tarragon underneath skin of each breast side. Using, twine, tie legs of chicken and wings.
Place breast side down in pan. You should hear a sizzle. Turn over with tongs, after 30 minutes. Roast another 30 minutes, using a meat thermometer. You want the chicken (at the thick part of the thigh) to reach 170 degrees. Take out and allow to rest for 15 minutes.