Cut English Muffins or bread into croutons (should fill 6 cups).
Place croutons on a cookie sheet, then sprinkle with poultry seasoning, parsley, and a little olive oil.
Bake in 350-degree oven for 30 minutes. Every 10 minutes, check the bread and turn, shake, and move it around to allow bread to brown evenly. When browned to the color you like, remove from oven. Can be frozen or refrigerated until needed.
When ready to use, melt butter and sauté vegetables gently until soft, about 8 minutes.
In a large bowl add bread, celery-onion mixture, and mix thoroughly. Cover and chill for at least 1 hour or make the day ahead. Put in a zip-lock baggie to store (one less dish to wash).
When ready to roast the turkey, fill it with the cold or room temperature stuffing. Roast the turkey until meat thermometer reads 165 degrees.
To make outside a turkey:
Place stuffing in a buttered 2 or 3 quart baking dish. Sprinkle 1⁄4 cup chicken stock on top, cover with foil and bake at 375 degrees for 15 minutes. Add an additional 1⁄4 cup stock and continue baking for 15 minutes. Add an additional 1⁄4 cup chicken stock, leave the dish uncovered and bake 15 minutes more. Total baking time is 45 minutes.