This is a long shot, I hope you like a challenge.

I heard a song in a cafe today, but I can't seem to find it on the t'internet. (Google seems insistant that I'm looking up La Marseillaise).

It sounded like a recent song, and was a duet with a woman singing in English and a man in French.

Most of the chorus was no help, it litrally was "da dada da dada" (or something like that). However it did have the line "Today is the [missing lyric] day". Not sure if the missing word was 'best' or even 'Bastille'.

Any ideas?

Forgot to add, it was sort of a jazz type song. At first I thought it was Caro Emerald, but it wasn't her singing.

Ahh, my initial thought was Youssou N'Dour & Neneh Cherry - 7 Seconds

https://www.youtube.com/watch?v=wqCpjFMvz-k

...but then you say jazz which probably rules this song out then?

I was guessing "da dada da dada" was for syllables and you couldn't think of the lyrics!!!

haha no, those were the actual lyrcis!