Heat oven to 325°F. Remove giblets from neck cavity. Release legs from wire band and remove neck from body cavity. Rinse turkey inside and out.
If stuffing, loosely pack neck and close with toothpick. Loosely stuff body cavity; tie legs together with twine. Tuck wings behind breast. Place turkey, breast-side-up, on an oiled rack in a shallow roasting pan.
Brush with oil and season with salt and pepper. Roast approximately 3 to 3-3/4 hours if unstuffed and 3-1/2 to 4 hours if stuffed. When skin is golden brown, loosely cover with foil to prevent overbrowning. Turkey is done when an oven-safe or instant-read thermometer registers 180°F in the thickest part of the thigh (not touching bone) and 160°F in the center of stuffing. Let turkey rest 20 minutes before carving to allow juices to redistribute.
Pour off fat and juices from roasting pan into a large measuring cup; let fat rise to the top. Spoon 3 tablespoons fat back into pan; place over medium heat on front and back burners. Add flour; cook 2 minutes, stirring constantly. Skim off fat in measuring cup; measure amount of juice left, and chicken broth and enough water to make 3 cups liquid. Pour into pan. Cook 5 to 8 minutes, stirring occasionally, until gravy is thickened. Makes 3 cups
Nutrition per 3 tablespoons: 45 cal.; 1 g pro.; 4 g fat; 2 g carb.; 0 g fiber.