The Chinese Chippy Delicacy the Rest of the World Is Missing Out On

There are a lot of things Scousers do differently to the rest of the world. Lads don't carry wallets, "steaming" means something else entirely, and we're couched in a cluster of red seats in a country that seems to think very differently to us on pretty much everything.

Another thing that sets Liverpool apart is its chip shops, which are – almost without exception – Chinese chippies. These, of course, are not exclusive to Liverpool – but I'd wager we have a higher density of them here than anywhere else in the country; walk into any fish bar in the city and you can be guaranteed a portion of siu mai with your fish supper.

One of the best consequences of our Asian-inspired chip shops is salt and pepper chips, a dish that's so run-of-the-mill in Liverpool you almost forget it's not universal – but I'd wager you'd have a hard time finding them in any fish and chip shop south of Nottingham. Born of the successive waves of immigration which helped build this port city, salt and pepper is heavily influenced by Chinese migrants who came to Liverpool looking for a new life in exchange for some really great chips.

Salt and pepper seasoning is a mix of onion, green pepper, chilli, salt and a concoction of other ingredients. It's equal parts sweet, savoury and salty, and you can lash it on anything from chicken nuggets to sausage rolls. Salt and pepper is so well-loved – and so prolific – that fierce debate exists around who's doing it best.

Scousers are proud tribalists. Whether it's Red or Blue, North end or South end, Liverpool is a city with an immense amount of pride surrounding the things it cares most about. Naturally, one of the things it cares most about is food. Arguing that your nan does a better pan of Scouse than other, lesser nans is a hill that most of us are willing to die on. But this tribalism is perhaps most pronounced when it comes to the local chippy.

Ask anyone in Walton and they will tell you that Byrne's is the best in the whole of Merseyside. And maybe they're right. But in Aigburth, Steve's is the only choice, while in Mossley Hill, Chris's Chippy reigns supreme. The latter, a Rose Lane fish bar that's been going since 1967, claims to do "the best salt and pepper in the world". Opened by Chris Moustoukas, it was one of the first takeaways in Liverpool to start offering salt and pepper, after a "master chef" brought his recipe along in the late 1960s.

These days, Chris's is run by Tony and Costa Moustoukas, the second generation sons of this chippy dynasty. Costa, who's 56, has been working at the fish bar since he was a teenager – and his recipe for "the world's best" salt and pepper is a secret he keeps closely guarded. Along with the usual peppers, onions and chillies, Costa adds in four extra secret ingredients which he claims make his salt and pepper chips more juicy than the usual dry seasoning mix.

"It's the mix that we create ourselves, which is very closely guarded," he told me. "It's vaulted. Even the chefs aren't allowed to know."

Like a Greek-Cypriot version of the Colonel, Costa's original recipe has made salt and pepper one of the most popular dishes on Chris's extensive menu. "[Customers'] jaws drop when you give them a taste," says Costa. "They look at you like you've got two heads on and then say, 'Wow.' I say to them, 'It's fantastic, isn't it.'"

Costa takes genuine pride in what he does, treating every chippy tea with the respect and importance it deserves. To him, this isn't just a quick takeaway meal, it's a craft. "Scousers are very fussy eaters, and you can't pull the wool over a Scouser's eyes – you've got to be the best at everything you do," he says. "It's an amazing flavour – not just the seasoning, the added juiciness and the three to four ingredients that we add. It's like a party in your mouth. It's salty, sweet, savoury and all that."

Although he wouldn’t reveal what actually goes into the mix, Costa did show me how he cooks his salt and pepper, taking the wok off the gas three to four times to ensure each ingredient is cooked to perfection. Onions and peppers are cooked off, with different ingredients added in batches to make sure the fresh chillies don't burn.

While Costa might be a master of the dish, its popularity extends to every chippy in the city. The last few years have even seen the rise of the "salt and pepper box" – a working man's mezze of chicken wings, siu mai, spring rolls and chips, all seasoned with the flavour.

A lot of things change when you leave Liverpool: people start calling their tea "dinner", like utter psychopaths – and saying "take your own" in the pub becomes meaningless. But the biggest blow is that, beyond L36, chip shops are just a pale imitation of the world champion standard we've grown used to.

@emiliabona