Wiktionary
soup du jour
n. Soup of the day; today's soup; whatever soup is sold under that name.
WordNet
soup du jour
n. the soup that a restaurant is featuring on a given day
Usage examples of "soup du jour".
On the rare chance you have an appetite when you emerge, lo, a Summer-Kitchen, complete with gesticulating Chef, Yes yes, Soup du Jour, Armand!
I'd be honored to be an ingredient with you in the same soup du jour.
Lifting a lid, she ladeled out a small portion of the soup du jour.