Remove the neck and giblets from the fully thawed turkey. Tuck the wings underneath the turkey or tie them back, if desired.
Pat the turkey completely dry with paper towels.
Combine the kosher salt and black pepper in a small bowl. Rub the seasoning inside the cavity and over the entire outside of the turkey.
Let the seasoned turkey sit at room temperature for 1 hour.
Preheat the oven to 425°F and position an oven rack in the lower third of the oven.
Trim the ciabatta loaf so it fits underneath the turkey. Slice the loaf horizontally and spread the softened butter over the cut sides.
Place the bread halves side by side in the bottom of a roasting pan with the buttered sides facing up.
Place the turkey breast-side down on top of the bread.
Roast at 425°F for 45 minutes.
Carefully remove the pan from the oven. Using sturdy tongs or two wooden spoons, turn the turkey so it is breast-side up.
Pour the chicken broth into the roasting pan around the turkey and reduce the oven temperature to 350°F.
Continue roasting for approximately 2–3 hours, basting with the pan juices every 20–30 minutes.
Cook until the thickest part of the breast and thigh reaches at least 165°F. Cooking time will vary depending on the turkey’s size.
Remove the turkey from the oven and let it rest for 30–60 minutes before carving.
Transfer the turkey to a serving platter, carve, and serve.
Notes
To thaw a turkey properly, allow 24 hours for every 5 pounds of turkey to thaw in a refrigerator.Refrigerate any Leftover turkey in an airtight container for 4-5 days.