For beef au jus, gather 1 beef rib roast or other roasting section, 1/2 cup red wine, 2 tablespoons mustard, 5 cloves garlic and 2 teaspoons Worcestershire sauce. Organize 1/4 cup peppercorn-garlic marinade, 1 cup beef broth, salt and pepper. Develop the pan juices immediately after the roast is extracted.
Make several slits about 3 inches apart in the roast with a paring knife, and place the slivers of chopped garlic inside them. Rub the mustard, preferably a spicy brown variety, over the entirety of the meat with a pastry brush, and pour the marinade over top. Cover the entire roast with tin foil, and bake at 350 degrees Fahrenheit until the meat thermometer registers an internal temperature of 130 to 135 degrees.
Remove the meat from the roasting pan, and tent it under the foil. Place the roasting pan on the stove top over medium-low heat, and add the Worcestershire sauce and red wine. With a spatula or spoon, scrape the brown elements from the bottom of the pan, integrating them into the au jus. Allow the contents to achieve a simmer, add the broth, then reduce the heat. Once the au-jus has thickened a bit, taste for seasoning, adjust, and serve with the rib.