There was a Restaurant about 5 mi. up the Coast from here that had one of those, too... but sadly, when I went to search for a photo of it, I found out it had been closed in Nov. and torn down to make way for 'development'...
They used to have a HUGE burger (2 lbs. I think) called the Desperado, that was meant for 4 people to share... and if anybody could eat the whole thing by themselves they would get it for FREE!!
There was a wall of pics for the folks that had actually done it...
RIP Outlaws