More like "quanta questa il zervezo sennoritay"-type tourist Spanish that optimistic, self-secure Americans often employ, while confident they are speaking as fluent as any Madridian.
I'm a Beaner you stupid Frog!! 
Are you one of those upper-class beaners who fled their country because they could no longer live in mansions owning half a province?
It's odd to see you using slur.
I never actually considered it a slur...
My spanish teacher introduced us to the term via the song (below). The way she explained it I got the impression that a long time ago most latinos in the southwest were migrant beaners, so thats where the term came from and that it started to be used as derogatory for all latinos. But then she seemed to imply gringo was not racist, its just what people call each other, and that in the southwest friend can use the terms beaner and gringo to refer to one another. But I could have misinterpreted everything.
No one around where I live calls anyone a beaner or a gringo.
