On a recent Sunday afternoon, Frenchmen Street was relatively tranquil. People still were sleeping off the night before or finishing up late-day brunches to quell any lingering after-effects. Strains of jazz – an accordion, clarinet, tuba – leaked onto the street. Rainbow-bright clapboard houses competed with the brilliant blue of the sky.

But the most New Orleans detail of all was the paper cup I was holding. No, it wasn’t a hurricane, that noxiously sweet rum cocktail every tourist sips through a straw at least once during their visit. It was the opposite: a remedy, affectionately dubbed ‘Old Sober’, said to right even the worst symptoms of fun.

Despite how I’d been served it, it wasn’t a drink. It was a soup – sort of. More spaghetti than broth, this version was heady and potent, kicked up with a triple Sriracha-Crystal hot sauce-Tabasco threat, and laden with juicy, coin-sized chunks of alligator meat. Of the latter, New Orleans native Linda Green, better known as Ms Linda the Yakamein Lady, put it best: “He look like a mean character, but he's a beautiful piece of meat and a delicious piece of meat.”

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Yakamein (pronounced ‘YAH-kah-main’) is one of those foods that, if you weren’t born and bred in New Orleans, you’re sure you’ve never heard of in your life. And then, with equal certainty, you suddenly know you can’t live without it ever again. But live without it most of us must.

Yes, it sounds simple enough to make at home – especially as the most common version uses beef, a useful alternative if you, like me, don’t have easy access to alligator (something that very much surprised Ms Linda when I told her). Boil leftover cuts of beef (extra authenticity points if they come from a Sunday roast cooked for family and friends). Simmer with salt, black pepper and garlic powder. Layer cooked spaghetti, tender bits of beef, chopped green onion and a boiled egg in a bowl or cup. Pour on the broth, give it a shake and let the flavours meld. Add extra hot sauce, if you want. Presto: yakamein.

When you taste yakamein, you come back to life

But like any fiercely local dish, yakamein almost doesn’t make sense outside of New Orleans. And not just because it’s both answer and antidote to the city’s fun-loving (and drink-swilling) attitude. It’s also that its flavours are brewed from the Big Easy’s multicultural web, and its cup-and-slurp style speaks to the city’s warm, down-home lack of pretension.

The dish’s legendary status even plays, in part, on the city’s black magic beliefs – because ‘Old Sober’ is more than a cute name.

“Sometimes, you know, you just out of it. But when you taste yakamein, believe it or not, you come back to life,” said Ms Linda. “My daughter, she might go out with her girlfriends, and she’ll come in in the morning – Maaaa, I need a yakamein. Maaaa, I need a yakamein. And I have to go get it.”

Like so much in New Orleans, yakamein is a hodgepodge and, because it’s a hodgepodge, difficult to investigate. “Nobody can pinpoint exactly where it came from,” said New Orleans native John Bel, one of a growing number of chefs to offer yakamein on the menu at his upscale restaurant Meauxbar.

It’s thought to be a fusion that resulted when Chinese immigrants and African-Americans blended homes, kitchens and ingredients in the early 1900s. But others say it developed further after World War II, or maybe the Vietnam and Korean Wars, when soldiers returned from the Pacific Theatre with memories of hot noodle soups.

Yakamein almost doesn’t make sense outside of New Orleans

Adding to the confusion is that there are yakamein-like soups elsewhere. Pho has similarities. So does ramen. And you’d be forgiven for thinking the closest variant, which hails from south-eastern Virginia, might even be the exact same thing. After all, it’s called yock – short for yock-a-mein. But yock-a-mein comes in a Chinese take-out box. It uses lo-mein egg noodles, not spaghetti, and often features sausage and white onions, which yakamein does not. Instead of hot sauce, ketchup is key, vinegar optional. Chinese immigrants may have played a role in developing Virginia’s version too, but the dish itself looks – and tastes – altogether different.

And so, except for die-hard foodies or fans of Anthony Bourdain’s No Reservations (which featured Ms Linda in 2011), yakamein is little known outside of New Orleans. When I mentioned to a couple of Baton Rouge residents that I was writing a story about yakamein, they had no idea what I was talking about.

“Very few visitors have heard of it. Some people, when they’re a foodie or are in New Orleans to eat, they’ve at least heard of it – but they don’t quite understand what it is,” Bel said.

What everyone agrees on, though, is that no matter who began cooking yakamein or exactly when, it came from family kitchens and the streets. As well as being made at home, yakamein was sold outside jazz bars and on the sides of second lines, the parades of dancing, singing celebrants that got their start as funeral celebrations.

This, as well as New Orleans’ general lack of pretension, also explains the local etiquette for eating yakamein: other than slurping it down in someone’s kitchen, the most authentic way to enjoy it is in a to-go container. Spoons not only aren’t required, they’d be a hindrance.

Bel’s version of yakamein, served up at Meauxbar, came from similarly down-home roots. One of the prep cooks used to bring yakamein to the restaurant for her lunch. Then she started sharing it with the staff. Then making it at staff meals. It didn’t take long for the recipe to wind up on the menu, where now it’s a daily favourite.

Meauxbar’s yakamein is good: layered with the umami of soy sauce, a heavy hand of celery and a dash of Worcestershire, it’s made of more broth than others. (Partly for that reason, partly because of the upscale bistro surroundings, I used a spoon for this one – or tried to).

But later, when I think of New Orleans yakamein, it’s Ms Linda’s version I remember. I’m not alone. Ms Linda is famed for dishing out thousands of cups of yakamein out of the back of her pick-up truck at second lines, the French Market, Jazz Fest and Mardi Gras. (Word to the wise: if you are going to ask Ms Linda how much yakamein she sells each Jazz Fest, don’t do it while you have a mouth full of yakamein. “Oooh. Oh my God. There’s a lot. It’s a lot. It’s over – 25,000?” Cue me spluttering soup. “Oh, don’t choke!”). Ms Linda cooks everything: etouffee and gumbo and jambalaya and beignets. But the recipe that she learned from her mamma, who learned it from her mamma, is yakamein.

Her traditional recipe uses beef. But not only. “I do alligator. I do crawfish. I do oysters. I do pork,” she said. She’s made sushi yakamein, jerk chicken yakamein and even yakamein-flavoured Bloody Marys. There’s a vegetarian version, too.

Spoons not only aren’t required, they’d be a hindrance

Ms Linda’s complex and rich broth uses two special ingredients. The first might sound like a marketing cliché except she believes in it so fervently, it’s hard not to be persuaded: “I put a lot of love into my cooking. A lot of it. Yes, I do.” The second (which she’s hinted is likely a mix of ingredients), inherited from her mother and grandmother’s recipes, she’s sworn even her family to secrecy about, complete with NDAs.

Whatever her trick is, the result is obvious. “It’s good,” Ms Linda confirmed for me after I took my first slurp, a look of happy surprise on my face. “Sometimes I eat that yakamein and I say to myself, ‘Oh Lawd, who made this!? This tastes so good, who made this!’” Who made it, of course, is Ms Linda.

In the middle of my conversation with Ms Linda at Bywater Bakery – the only place where you can find her yakamein regularly, outside of pop-ups – her phone rings. “Hey, baby,” she said. “One yakamein? Okay. I’m busy right now, honey. I’m busy right now, but I be home in an hour. Get someone come to come pick it up, okay? Okay, baby.”

“One of your kids?” I asked with a smile. “Oh, no,” Ms Linda said. “I don’t know who that was.”

This, it turns out, happens all the time. People get Ms Linda’s number and call her when they need a yakamein fix. She used to drop it off for them. She doesn’t do that anymore. Instead, she’ll prepare it and leave it for her hungry customer to collect. And, she said, she won’t ask for them to pay. “Oh, Amanda,” she said. “This is my problem.”

Ms Linda’s phone rings with particular frequency on Sundays.

It turns out that this belief in yakamein’s transformative effects is more than faith. In a conference talk a few years ago, food scientist Alyson E Mitchell said that, indeed, yakamein likely helps hangovers. Eggs have cysteine, an amino acid that helps scrub acetaldehyde (one of alcohol’s toxic by-products) from the body. The fatty meat can help slow down the absorption of alcohol, making yakamein an equally good choice before a night out as it is after. The salty broth replaces the sodium lost during all those alcohol-induced trips to the toilet; it also encourages you to drink more water, fighting dehydration.

“It may be a good example of intuitive science: an effective remedy, with the scientific basis revealed only years later,” Mitchell said.

Later, I wind my way down Bourbon Street. It isn’t evening yet, but the street has that surreally unchanging sense of a party that never stops: 5pm or 5am, the lights are neon and the music is playing. Some African-American kids are enthralling a crowd, drumming an electric beat onto paint tins. A group of white 20-something women are striding down the street in tutus. An elderly couple stroll with walking sticks, Mardi Gras beads looped around their necks.

The night is young. Every option feels open. A jazz bar, or happy hour oysters? I’m not sure, but I do know one thing: tomorrow, I’m going to find myself some yakamein.

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