Preheat the oven to 325°F. Liberally grease a 2 1/2- to 3-quart casserole dish with nonstick cooking spray and set aside.
Place 1/2 cup of the chicken broth in a medium skillet, and place over low-medium heat. Add the celery and onion and sauté for 5 minutes, or until the vegetables are tender.
Combine the sautéed vegetables with the stuffing mix, cranberries, egg whites, parsley, poultry seasoning, and salt in a large bowl, stir in the remaining 1 1/2 cups of chicken broth.