These famous green huts with kitchens were founded in the 19th century by The Cabmen’s Shelter Fund, as pit stops for black cab drivers in need of a cup of tea and fried breakfast. Now only 13 of 61 original huts remain, with 10 open for business. Only cabbies are allowed to take a seat inside, but they’ll serve anyone through the hatch. The sandwich is a basic arrangement of bacon, sliced white, butter and sauce, which hits the spot as only a no-nonsense breakfast sandwich can.

The Sub Contractor from itinerant sandwich merchants Sub Cult is the platonic ideal of a breakfast sandwich: super easy to eat, just the right size and packed with carefully sourced and cooked elements. The bacon and herby sausages come from The Butchery, a free range egg is cooked to customers’ preference, and there’s white pudding, ketchup and a subtle truffle mayo which adds just a hint of mushroom-umami. The bread is special: a hybrid bagel and brioche dough made to order by Whitechapel bakery Rinkoff’s.

The Convict sandwich at Balham’s exemplary breakfast spot definitely falls into the ‘extra’ category. Oak-smoked belly bacon from Tamworth pigs is layered with a secret-recipe sausage patty, ‘folded eggs’ from a Gloucestershire farm, and ‘hangover sauce,’ which is a smoked chipotle ketchup. A final flourish of grated Lincolnshire Poacher and the stack is complete. Follow with a nap on the sofa.

Lee Tiernan’s Highbury and Islington restaurant was never going to serve a straight up bacon sandwich. This is a delicious mess, which starts with a base of house-cured bacon on a butter-slathered flatbread. XO slaw comes next, the cabbage and lettuce dressed in an electric mixture of shrimps, chilli, shallots, garlic and spices, followed by pickled chillies, crispy hot dog onions, coriander and shoestring fries.

Le Swine specialise in bacon butties — an admirable pursuit. Thick-cut Middlewhite bacon sourced from a family butcher in Lancashire is served on a milk and onion bun with bacon butter, mushroom ketchup and an optional — but highly recommended — fried duck egg. It squishes down into an easily manageable whole, unlike the overstuffed competitors splurging their contents with every bite.

Coal Rooms’ breakfast bap divides opinion among locals. The restaurant is owned by coffee roasters Old Spike, and as such does a roaring morning trade in commuter coffees; leftover milk is used to make buns. On a good day, these are a soft, springy and pleasantly chewy casing for thick-cut bacon and plenty of it.Choose from back, streaky or a mixture of both, and make sure to ask for extra sauce.

Possibly the polar opposite of the greasy spoon style, these perfectly round and shiny bacon buns are available on Hackney Road on Sundays. Tamworth or Gloucester Old Spot pigs are cured and smoked in house and the meat is braised with cider, spices, shallots and bay, before being stuffed into buns. Inspired by the Victorian street sellers of the East End, they are baked then steamed for the perfect texture.

Charlie’s is a pop-up side project for street food sandwich slingers Project Sandwich, most recently found at Victoria Park Market. The Bacon begins with a Beigel Bake beigel toasted in salty pan drippings, filled with maple-cured bacon, ‘spud scraps,’ which resemble the naughty, crusty edge bits of a rosti, and a duo of sauces: homemade hickory ketchup and Sriracha mayonnaise.

The Dusty Knuckle is among the cream of London’s sandwich shops, so an exceptional bacon sarnie is de rigueur in Dalston. It’s all about that exceptional potato sourdough, topped with a substantial tangle of free-range, native breed streaky from Swaledale Foods. It’s huge, like all the sandwiches, so either power through the morning or crawl back to bed.

Quality Chop House’s Clerkenwell shop uses both smoked and unsmoked bacon for the perfect flavour profile, made from Yorkshire bred Tamworth pigs which are cooked until so crisp that the belly almost shatters with every bite — perfect for those with a fear of flabby fat. Bread is Bermondsey bakery Little Bread Pedlar’s white pan loaf, and sauce a choice between house-made ketchup or good old HP.

Those who find themselves wanting more than bacon should try the Bob’s Your Uncle from Brother Marcus. Substantial slices of pork belly replace traditional rashers, accompanied by a fried egg, spring onion, tomato relish and a squiggle of Sriracha for that all-important lip tingle. A Cretan pitta is delicate yet sturdy enough to hold out to the last bite.