Turn turkey giblets and canned chicken broth into a rich stock to enhance the gravy and stuffing. Don't use livers in the stock - they make it bitter and cloudy. A cleaver works best to chop the neck. Make this up to 2 to 3 days ahead so it will be ready to use in the Farmhouse Roast Turkey with Rosemary Gravy, Sausage and Mushroom Stuffing, and Broccoli and Carrots with Toasted Almonds.
Heat oil in a large stockpot or Dutch oven over medium-high heat. Chop neck, heart, and gizzard into 2-inch pieces; add to pan. Cook 5 minutes or until browned, stirring occasionally. Add onion, celery, and carrot; cook 4 minutes or until tender, stirring frequently. Stir in the water and broth; bring to a boil. Add thyme, peppercorns, parsley, and bay leaf. Reduce heat, and simmer 2 hours. Strain the mixture through a sieve over a large bowl; discard solids. Cool to room temperature. Cover and chill overnight. Skim the solidified fat from surface, and discard fat.
Note: Refrigerate leftover stock in an airtight container for 2-3 days, or freeze for up to 3 months.