Like many great ideas, the Manchester egg began in the pub.

Ben Holden was enjoying a few pints in bohemian Oldham Street boozer, the Castle, when he ordered a pickled egg, some Seabrook salt 'n' vinegar crisps and, from the Castle's pie warmer, a scotch egg. For the web designer and enthusiast amateur cook, this snack would prove a revelation.

Playing around, Holden ate a little pickled egg together with a slice of warm, moist savoury scotch egg. Then he started dipping pieces of pickled egg into finely crushed crisps, revelling in the texture contrast of the crunch and the rich, yielding firmness of the egg white. Convinced that, "that pickled flavour dimension is that extra level that the scotch egg has always missed", he went home that night determined to fuse the two: "If I have an idea like that, I'm more than happy to dive in and experiment."

A few weeks later, Holden was back at the Castle for a mate's birthday, where he unveiled the prototype 'pickled' scotch eggs. After several trial runs, he had settled on a pickled egg, wrapped in a mixture of rare breed pork meat and, that local Lancashire favourite, black pudding, coated for maximum crunch in Japanese panko breadcrumbs - to be served warm. Holden's mates, and soon the whole pub (the Castle is a very gregarious kind of drinking hole), went wild for these new style eggs, in which the fulsome blood sausage is artfully offset by that pointed vinegary pickle.

By the night's end Holden was promising to fry up a new batch for the following Friday and over a few weeks in January and February this creation - now christened the Manchester egg - became a minor local sensation. Holden was selling 30 or so eggs every Friday lunchtime, with people schlepping across town to try one with a pint of Cumbria Way.

With demand already outstripping supply and the eggs taking over Holden's home - "my missus was going mental about it smelling like a chippy" - he had to have a rethink. In April, production was moved to the newly relaunched Soup Kitchen, where after some training French chef Amaury Neury became the custodian of the Manchester egg.

The Soup Kitchen is serving the eggs (at £2.50) on Thursday, Friday and Saturday, accompanied by a sweet fig chutney. Although Holden does have plans for a partner Manchester relish. He dubs it an "open sauce" project - with a collection of friends tasting and chipping in with suggestions - but the current recipe is evolving around a fruity base of caramelised red onions and Vimto. Says Holden:

"It's about time Manchester had a new namesake food stuff, that it can really call its own. No-one has tried it since, probably, the Eccles cake. I just though, 'why not? Let the people have an egg'. And I've thought about the legacy. If I can establish a new type of basic Manchester foodstuff, this might live longer than me."

The Manchester egg, of course, is in a fine tradition of British culinary hybrids. Chicken tikka masala, scouse (originally a Scandinavian seaman's dish) or - much discussed on this board - Middlesbrough's parmo are typical of such cultural cross-fertilisation, while Scotland has almost cornered the market in such localised 'innovation', with its haggis curry, 'haggis' chocolates, deep-fried pizzas and, even, a deep-fried sausage-kebab combo, the Stonner.

Nationally, meanwhile, unique local food products are enjoying a significant resurgence. The likes of Melton Mowbray pie and Lincolnshire sausage makers have been fighting for protected status, while a rash of newer products make great play of their geographic provenance, even if they rarely ring 100% true.

Welsh Red Mustard gets pretty close, given its uniquely sweet and red, is made in Wales and to a new Welsh recipe. But it doesn't utilise distinctly Welsh ingredients, or riff on a Welsh food tradition. Yorkshire Tea, in contrast, is a triumph of marketing (the association of gruff Yorkshiremen with strong tea) over reality. The tea might be blended in Harrogate, but - for now at least - it's grown in far flung places, and, surely, a 'builder's tea' blend is the default of most tea brands, from PG Tips to Typhoo? It's hardly unique.

The Manchester egg, though, is the real deal: a genuinely new product, using genuinely 'northern' ingredients which surely deserves its places among the pantheon of regional foodstuffs, alongside Cornish pasties and Cumberland sausage. What similarly convincing new food and drink creations are out there, and what would best represent where you live?