This Spatchcock Cast-Iron Mustard Chicken will quickly become a favorite, I know I find myself making it over and over again. It's a staple meal you'll enjoy again and again.
Mix all the ingredients (except the chicken) in a bowl.
Put 2 tbsp of the mixture under the skin of each breast. Put 2 tbsp of the mixture under the skin of each thigh.
Heat your cast iron skillet on the stove. Add a thin layer of oil, if necessary*. Add 1/4 of the remaining mixture to the non-skin side of each chicken half and place the chicken skin side up in the pan. Add the remaining mixture on top of the chicken. Cook 5 minutes until starts to brown. Transfer to the oven.
Cook 30-35 minutes in the oven until internal temperature reads 155F when checking the inside of the chicken breast.* It will continue to cook while it rests. Let rest 5 minutes before serving.
Notes
*If your pan is well seasoned you may not need additional oil. *Internal temperature of chicken should reach 165F.Clean your cast-iron skillet immediately after use. If the drippings and food residue does not wipe out easily, use hot water to hand-wash your cast iron. Then, you can use an abrasive sponge to scrub off any stuck-on food. Next, use coarse kosher salt to scrub off any remaining if necessary. Finally, dry the skillet thoroughly, add a thin layer of oil, and re-heat the cast iron. Once it cools you can store it until your next use.
Do not cover the chicken, or the skin will not get crispy.