The Burger Born in Sasebo
This iconic burger was born in 1950, after U.S. forces stationed in Sasebo introduced the recipe for hamburgers to the locals. There are no set rules for the construction of a Sasebo Burger, however—in essence, it just needs to be made using ingredients from Sasebo.
How representative is this burger? Well, you'll find Sasebo Burgers on signs in JR Sasebo Station...
...And you'll find the Sasebo Burger Boy mascot at the information center as well.
The design was prepared by none other than Takashi Yanase, creator of Anpanman, a massively popular children's character who has a sweet bean bun for a head (not to be confused with the actual Anpanman character with a less specific hamburger for a head).