a burger acquired from an unverifiable source, such as as a late night snack following kicking out time at a nightclub. Usually sold from a mobile kitchen. Often very worthwhile - they can be tasty, filling and inexspensive, especially when sold in daylight hours on main roads to sober drivers and passengers, but when sold to drunks after midnight will probably consist of stray cats and toast. Origin - Midlands, UK.
next little chef is about ten miles up - wait - Pull over! pull over! it's the dirty burger van! We're saved!