Preheat your oven to 400 degrees Fahrenheit. Remove the chicken from the refrigerator and pat it thoroughly dry with paper towels. Drying the skin is the most important step to ensuring it becomes crispy rather than soggy during the roasting process. Place the red onion wedges in the bottom of a large roasting pan or a heavy cast iron skillet.
In a small bowl, mix the softened butter with the minced garlic, chopped rosemary, salt, and black pepper. Gently loosen the skin over the chicken breast and rub half of the butter mixture underneath. Rub the remaining butter all over the outside of the chicken. This ensures the meat stays juicy while the skin seasons perfectly.
In another small bowl, whisk together the maple syrup, apple cider vinegar, and chicken broth. This mixture will act as both a basting liquid and the base for a delicious pan sauce. Place the chicken on top of the onions in the roasting pan and pour half of this maple mixture over the bird.
Place the chicken in the oven. After 30 minutes, scatter the cranberries around the chicken in the pan. Pour the remaining maple mixture over the chicken and cranberries. Continue roasting for another 40 to 45 minutes, basting the chicken with the pan juices every 15 minutes. This helps build that deep, golden color we want for Christmas dinner.
The chicken is done when an instant-read thermometer inserted into the thickest part of the thigh reaches 165 degrees Fahrenheit. Once finished, remove the pan from the oven. Transfer the chicken to a cutting board and let it rest for at least 15 minutes before carving. This allows the juices to redistribute, ensuring every bite is moist.
