Combine all ingredients except cornstarch or arrowroot in a 4-quart pot. Bring to a boil over medium heat, then lower heat and simmer for 10 minutes.
At serving time, disolve thickener in 1/2 cup cold water. Bring the gravy to a low boil. Slowly pour in the thickener and stir whie the gravy turns from milky to smooth and thick. Add enough thickener to reach the consistency you desire.
Note: Poultry seasoning does not contain animal products. If you don't have poultry seasoning, use 2 to 3 tsp of a mixture of rosemary, sage, thyme, marjoram and basil.
Servings: 8 cups