A day or two before you plan to make the stuffing, cut the bread into pieces and set out in a pan to stale, stirring once or twice a day to rotate the pieces.
If the bread pieces are not already staled, toast in the oven until at least half of the pieces are quite firm and crunchy.
Pre-heat the oven to 325 degrees.
In a large pan, sauté the onions and celery in the butter until soft enough to cut easily with a spoon.
Add the spices and stir well to combine.
Place the bread pieces in a large, sided baking pan (such as a lasagna pan) and pour the butter and vegetable mixture over the bread. Stir to evenly coat.
1 hour before the turkey is expected to be done, put the stuffing pan into the oven on the bottom rack.
Stir the mixture after 30 minutes, then place back in the oven for another 15 minutes.
Pour a small amount of the chicken stock (enough to get the texture of stuffing you prefer) over the stuffing and stir to combine.
Place back in the oven for the final 15 minutes.