Hmmm, the explanation about les haricots that I heard in some documentary about Preservation Hall was that the expression "couper les haricots" (cut beans), referring to taking the string off the string beans (haricots verts) and roughly pronounced in Africanized French as coopay lay zahdeeco [because of the liaison], meant to dance up a storm, and that's where the word pronounced zahdeeco if you have a French accent and spelled Zydeco backformed for the music to which you dance that storm up.

I love American syntax.