BRINING TURKEY: ONE DAY BEFORE baking turkey, prepare brine. Combine all the brine ingredients. Place the turkey in a bucket or very large pot and pour brine over turkey to submerge. Refrigerate for 12 to 24 hours. Remove turkey from brine; dry off turkey with paper towels. Discard brine.
Preheat oven to 300 degrees.
Brine turkey as instructed above. Salt and pepper the brined turkey and cavity. Fill the cavity with carrots, celery, apple, orange, and garlic; bind the legs with kitchen twine.
In a large roasting or braising pan (or disposable aluminum pan), spread onion, carrot, celery, garlic, sage, rosemary, thyme, parsley and bay leaves. Place the turkey on top of the bed of vegetables and herbs.
Put butter on turkey, or between skin and breast meat.
Place the turkey in the oven and roast 45 minutes. Pour half the chicken stock over the turkey; roast 45 minutes. Pour remaining stock over the turkey and roast 45 more minutes; it will start turning golden brown.
Baste with pan juices, cover loosely with foil and roast an additional 45 minutes. When the turkey has reached an internal temperature of 165 to 175 degrees, remove from oven, keep covered, and let rest at least 10 minutes before carving. Transfer to platter.
TO MAKE SIMPLE GRAVY: From the bottom of the roasting pan, discard herbs and measure out 1 cup of vegetables and 3 cups of pan juices; puree in blender. To thicken, add more vegetables; to thin add more pan juice. pour through a mesh strainer to make a smooth gravy. Makes 4 cups. TIP: For silken gravy, forget the flour. Avoid using flour, because that's usually what causes lumps. Instead, puree the vegetables you roast along with your turkey; they become your thickening agent. That, along with your pan juices, becomes your gravy. You can strain it through a mesh strainer, or use cream and reduce it.