Green’s Dictionary of Slang

ken n.2

[SE colloq. barbie, a barbecue; punning on Ken and Barbie, the fashion dolls]

(Aus.) a cleaning implement for a barbecue.

[Aus]G. Seal Lingo 81: The occasional complexity of the Lingo is well demonstrated in a widely used folk name for a barbecue-cleaning implement marketed as a BBQ-mate. These, and by extension any other such tool, are known as kens, derived from the name of Barbie’s friend, Ken. This is probably best conveyed through example: where’s the ken, i’ve got to clean the barbie.