People and restaurants have been replacing traditional burger buns with all kinds of things, which now includes a Scotch egg. This food item typically consists of a hard boiled egg that has been wrapped in sausage meat and covered in bread crumbs. It can be either deep fried or baked.
London food truck Say Yeah! Burger created the 'Marco Polo' -- a burger consisting of an aged beef patty, lemon aioli and a manchego-stuffed chorizo Scotch egg. They're also selling a burger called 'The Dragon,' which is a lamb patty sandwiched between a haggis and kedgeree Scotch egg with caramelized leeks and clamato beurre blanc.
Given that it is coming from a food truck, only limited amounts of these burgers are available on a daily basis.