Au jus in French means served with the natural juices or gravy made from the juices of cooked meat. In the US, meals served au jus tend to be defined as served with a light broth-like dipping sauce. One of the most well known of these meals is the french dip, a roast beef sandwich accompanied with broth.
Au jus broth tends not to incorporate much of the meat’s natural juices, but it is a good pairing with a roast beef sandwich. Typical ingredients in an American au jus include soy sauce, Worcestershire sauce, garlic, onion, and often beef broth. Sometimes, the broth is merely a beef bouillon. You can even purchase this broth in powdered form, which helps meat give off flavored juices. These may be skimmed from a pan after meat has cooked and brought to a quick boil.
Of course there’s no reason why you can’t make an au jus in the French tradition. When you cook your meat, and beef normally is best for this, simply skim off the juices. While you are boiling them, you may want to add a little garlic, some onion powder, a dash of soy sauce and some salt and pepper. You can make terrific french dip sandwiches at home with freshly made thin slices of roast beef on rolls.
Another popular meat served au jus is prime rib. Again in the American sense, this flavoring may be light gravy made completely independently from the meat. However, prime rib served in this way with authentic meat juices is quite tasty. There are several turkey recipes served with the juices, which can mean fewer calories. Still, if the skin of the turkey is left on and the jus is made from pan drippings, it will be fairly high in fat
Americans may use the term au jus incorrectly. The French word au translates to with the. Therefore when you serve something in this manner, it is incorrect to say you are serving the meal with au jus. This would translate to "with with the natural juices". Instead, meat is normally served au jus. The word with is already implied when using the French term, so there is no need to repeat it.