[KevinB]

The sandwich is dipped in a broth-like gravy called au jus that's made from the juices of the roasted meat.

"Au jus" is not a thing. "Jus" is the French word for "juice." "Au" is the French word for "with." "Au jus" means "with juice." It would make no sense to say, "I'll have that with au jus." One would instead say, "I'll have that au jus." There, I feel better now. :-)

[reasonisfaith]

Your attention to the meaning of words and how they’re used is much appreciated.

On a separate note, I just can’t relate to French words like “au” or “jus.” Like many other French words (other than the ones that have been successfully Americanized), I simply won’t be using them.