You will need to dry the bread cubes overnight; transfer them to resealable plastic bags until you're ready to make the stuffing, up to 1 day more. Cover; bake at 350 degrees for 25 minutes. Uncover; bake until hot and golden brown, 30 minutes more.
- 2 loaves good-quality white bread, cut into 3/4-inch cubes (about 20 cups)
- 1 1/2 pounds fresh chestnuts (4 cups), scored with an X
- 3/4 cup unsalted butter (1 1/2 sticks)
- 4 small onions, peeled and cut into 1/4-inch dice (about 3 cups)
- 1 bunch celery, cut into 1/4-inch dice (about 4 cups)
- 3 tablespoons finely chopped fresh sage
- 5 cups homemade or low-sodium store-bought chicken stock
- 1 tablespoon coarse salt
- 3 cups coarsely chopped fresh flat-leaf parsley
- Freshly ground pepper
Spread bread cubes in single layers on baking sheets. Let dry at room temperature, uncovered, overnight.
Bring a medium saucepan of water to a boil. Add chestnuts; cook until soft, about 20 minutes. Drain; let cool slightly. Peel and quarter chestnuts; set aside. Peeled chestnuts can be refrigerated in an airtight container 2 to 3 days.
Melt butter in a large skillet over medium heat. Add onions and celery; cook, stirring, until onions are translucent, about 10 minutes. Add sage; cook 3 minutes. Stir in 1/2 cup stock; cook until reduced by half, about 5 minutes.
Transfer onion mixture to a large bowl. Add remaining 4 1/2 cups stock, the chestnuts, bread, salt, and parsley; season with pepper. Toss to combine. If not stuffing turkey, transfer to a buttered 17-by-12-inch baking dish. Cover; bake at 350 degrees for 25 minutes. Uncover; bake until hot and golden brown, 30 minutes more.