Preheat oven to 375°F. Rub the chicken with garlic powder, salt, and pepper.
Heat the oil in an oven-safe skillet or sauté pan on medium high heat. Place the chicken skin side down in the pan until the skin is nicely golden brown and crisp. Flip the chicken over and transfer the pan to the oven and roast until a thermometer inserted in the thickest part of the meat, (not near a bone), registers 160°F, about 20 to 30 minutes. (Could be more or less depending upon size). Transfer the chicken to a carving board and let rest for 5 minutes. Reserve any juices leftover in the pan.
Heat a saucepan on medium heat. Add 1/3 of the butter and the shallots to the pan. Saute until soft, then add the leftover juices from the pan, cream, and orange zest. Bring to a simmer, add in the butter a little at a time while whisking constantly until the sauce becomes thickened and smooth. Remove from the heat and season with salt and pepper to taste.
Remove the breast bones and wishbone from the chicken and slice. Spoon the sauce the chicken and serve with bread. Garnish with rosemary.