Cut the brioche into 3/4-inch cubes and place it in a large bowl. Melt the butter in a large saute´ pan. Add the celery and onion and cook for about 15 minutes over medium heat until very soft.

Meanwhile, in a medium-size saute´ pan, cook the sausage, breaking it up into small pieces with a fork until it is cooked through, 4 to 5 minutes. Add the sage and saute´ with the sausage for about 30 seconds.

In a small saucepan, heat the chicken stock. Deglaze the sausage pan with about 1 cup of the chicken stock, scraping any bits from the bottom of the pan.

Pour the sausage–chicken stock mixture plus the remaining stock over the brioche. Add the celery-onion mixture and stir well. Add the cranberries to the stuffing and season with salt and pepper. Add more stock if the stuffing seems dry.