Preheat oven to 325 degrees F (160 degrees C). Remove the package of giblets and neck from the cavity of the Whole Turkey (12 pound). Rinse the turkey with cold water and pat dry with a paper towel. Tie the ends of the drumsticks together.
Place the turkey, breast-side up, on a rack in a roasting pan. Brush the turkey with Olive Oil (1 tablespoon). Season with Kosher Salt (1/4 teaspoon) and Freshly Ground Black Pepper (1/4 teaspoon). Insert a meat thermometer into thickest part of the meat.
Stir the Chicken Stock (1 package), Dried Basil (1 teaspoon), Lemon Juice (3 tablespoon), Dried Thyme (1 teaspoon) and 1/8 teaspoon additional black pepper in a large bowl.
Reserve 1 3/4 cups stock mixture for the gravy. Pour the remaining stock mixture over the turkey.
Roast at 325 degrees F (160 degrees C) for 3 hours or until the thermometer reads 165 degrees F. Baste occasionally with the pan drippings. Begin checking for doneness after 2 1/2 hours of the roasting time.
Remove the turkey from the pan, cover and keep warm. Spoon off any fat and pour off all but 1 1/2 cups pan drippings.
Stir the reserved stock mixture and All-Purpose Flour (1/4 cup) in a medium bowl until the mixture is smooth.
Add the flour mixture to the pan.
Cook and stir over medium heat until the mixture boils and thickens, scraping up the browned bits from the bottom of the pan. Season, if desired. Serve the gravy with the turkey. Enjoy!