Place the beef into a roasting pan. Roast at 350 degrees F for about 1 hour or until the beef is cooked through, basting occasionally with 1/2 cup stock. Remove the beef from the pan and keep warm. Pour off any fat, reserving 1 tablespoon drippings.
Stir the drippings and flour in the roasting pan. Gradually stir in the remaining stock. Cook and stir over medium heat until the mixture boils and thickens. Season to taste, if desired. Serve the gravy with the beef.