At the crack of dawn, over a shot of espresso, comes the revelation: sushi isn't raw fish.
"Su is vinegar and shi is short for rice, so it means 'vinegared rice,'" says sushi master Carl Ishizaki, head chef of Sushi Sho in Stockholm.
It's hellishly early and Ishizaki and I are at Billingsgate Market in London, on an all-singing, all-dancing fish trip—hence the discovery. Today, during his collaboration with Carousel, the London restaurant that hosts a travelling circus of guest cooks and chef-greats at its Marylebone restaurant, the Michelin-starred chef has come to check out the market.
"Originally sushi was an accidental fermentation," he continues. "Someone left rice in a fish belly. Nowadays that type is very expensive and fermented."
Finishing our caffeine hit in the market's caf, it's too early to eat the bacon butties the local residents are devouring with smears of ketchup. The smell of sea creature permeates the nostrils.
But for Ishizaki, discussing food at 5 AM isn't that unusual.
"I'm off to the Tokyo market next week. It's not long before it closes to the public," he says.
Every year, Ishizaki, whose Dad is Japanese, heads to Japan's capital. He explores the methods from the Edo era, predating refrigeration. He sees pickling, curing, and aging as an art.
And this sushi jedi's standards are high. Among Billingsgate trolleys and boisterous fishmongers, he is silent. I wonder whether he is sated or deeply unimpressed.
"That's sea bass. Over there is swordfish. And parrot fish," he points, when I ask him.
There are sardines and needle fish, but much of it is bewilderingly tropical.
In contrast, at Sushi Sho—Ishizaki's hole-in-the-wall 12-seater in Stockholm with a cult following—"there are no choices, just a menu. The ethos is local as possible. Fish like Arctic char and pike perch feature."
Its uncompromising approach has impressed. The restaurant recently won a Michelin star.
"The star was extremely unexpected," says Ishizaki. "It's not fine dining, it's not even that pretty—just a counter with a couple of seats."
Suddenly, "Out the way darlin'" comes hollering from a rogue trolley rattling towards us and an overalled bloke whizzes past, pushing boxes piled high with piscatorial treats. We—that's me, Ishizaki, and brothers Ollie and Ed Templeton, who co-run Carousel—ogle the trays.
The noise dissipates as he merges into the crowd and Ishizaki continues: "The firmness of flesh is a sign of freshness. If recently caught, it has rigamortis so it should be firm, unless it's killed the Japanese way where it's speared with steel thread down the spine. The eyes can't be sunken or cloudy either."
We wander the aisles but no purchases are made as Carousel has its coastline suppliers arriving direct to the restaurant soon. And so by 7 AM, we leave.
Striding through Canary Wharf's shadowy alleyways between the towers, Britain's once powerful financial city is oddly ghostly. We grab the Tube and head to Carousel for breakfast.
Back in the kitchen, Ollie cooks with Ishizaki to a banging eighties soundtrack from The Cure, Culture Club, and Pet Shop Boys.
They stab the langoustine in the back of the head. It's served virtually wriggling, bar a second of searing and drizzle of craft soy sauce and sake. The brothers tell me these clawed chaps are from Scotland Celtic Seafare.
Mackerel appears—salted, then cured in shio koji and plum vinegar—followed by fish offal, a favourite of Ishizaki. His monkfish liver, which comes next, is fish's answer to foie gras, rich and creamy but with fewer ethical issues—you're eating the whole animal, rather than wasting parts.
Ed and Ollie don't bat an eyelid at the master at work. If it's not one cheffy legend working this space, it's another. Over the next few months, says Ed, they've everyone, "from Niklas Ekstedt, the Swedish super chef to Danny and Yesoon Lee of Mandu in Washington DC, the mother and son duo reinventing traditional Korean cooking."
For each, the week at Carousel is a chance to have a dalliance with a new capital's culinary culture.
In a further few minutes, Ishizaki finishes off today with his signature soy cured egg yolk, okra, dusted with toasted rice. For Ishizaki, his stint in the UK has been about getting to know the indigenous seafood as much as anything. At the end, he says in his typically understated manner: "British seafood is good. Ollie has high quality."
I tend to agree.