It looks like the creepy advertising and food that was the hallmark of Burger King is now at Jack in the Box ... Jack ... I beg you ... go back to the sane, but funny commercials.
Anyway, according the this article in the Christian Science Monitor (of all places), you have to ask for it. It is not on the menu.
" If you’re keeping kosher or vegetarian, you’re in luck: The shake is made with bacon-flavored syrup, rather than the genuine article"