15 Kingly Street, London W1 (020 8181 8887). Meal for two, including drinks and service, £110

A damp winter’s night in January, and waiting for me by the door as I leave Jinjuu, a new glossy Korean restaurant behind London’s Regent Street, is the chef. Oh God. The night’s been tiresome enough as it is. And now this? There are good reasons why the chefs of restaurants I review don’t generally hang around waiting to shake my hand as I leave. Mostly it’s to do with all of us being terribly British and awkward. What if I hated the place? Am I supposed to grin at them like someone’s attached electrodes to my cheek muscles? Then again Judy Joo, a TV celebrity chef, is Korean-American. All this British-awkwardness stuff is probably lost on her. We mumble at each other, shake hands, and I leave.

And that should have been the end of it were it not for my decision to ask questions of Joo by email. I was merely trying to write an interesting article about what I had eaten for my tea; instead it turned into a costly legal drama, dragging in some of the biggest names in the British chef world and pointing up just how feverish the London restaurant scene is right now. Mind you, it was a damn sight more entertaining than the meal itself.

But first let’s deal with Jinjuu. Upstairs is a bar with music so loud it vibrates your colon, where they serve cocktails with irritating names like Gangnam Millionaire and Sake It To Me. Downstairs is the dining room, serving its own take on the Korean repertoire. It is for the most part serviceable, if expensive. Dumplings have light casings, but the portion is meagre for £6.50. Prawn balls have all the virtues of seafood that has swum in the deep-fat fryer. Boo Ssam pork belly, glazed and served with apple cabbage kimchi, is fine, if a little stringy. The fried chicken comes in a heavyweight batter shell, but we do like the accompanying sauces in their miniature squeezy bottles.

Korean advice: Boo Ssam pork belly with apple cabbage kimchi. Photograph: Sophia Evans for the Observer

The menu would insist it’s all much better than this. It’s written in the dribbling language of a 13-year-old’s Instagram account in which mayo is “addictive”. Prawn crackers are “bespoke” and apparently “awesome” with beer. Forgive me, but it takes more than a cracker and a pint of lager to fill me with awe. Waiters are desperate to explain the “concept” and are ever-present. What is the Korean for: “Do sod off and leave us in peace”?

Still, presumably Judy Joo knows her market. She began as an investment banker before swapping into the world of food and television. Her biography on her own website lists her two years working for Gordon Ramsay. Time spent at his flagship restaurant is mentioned again on the Jinjuu website. I ask Gordon Ramsay Holdings about her time with them. At this point it should be made clear that, from my subsequent enquiries, there is no doubt Joo did spend significant time working in the kitchens of the group, albeit mostly on an unpaid basis.

Which makes the GRH response all the more bizarre. You’d think I’d accused them of drowning kittens. Managing director Stuart Gillies told me that Joo was only given part-time experience as a gesture of goodwill at Restaurant Gordon Ramsay in the pastry section, that they have no records of employment for her in any of their other restaurants, and that at no point did Gordon Ramsay himself train her (which was not something she’d ever claimed). Gillies went on to accuse her angrily of being economical with the truth on her personal website.

Something sweet: the dessert sharing plate. Photograph: Sophia Evans for the Observer

Blimey. I was only looking for a bit of background. I put all this to Joo by email. I thought she might call me. I’d have liked that. After all, we met a few years ago. She even asked me for advice on getting into British food media. Instead her lawyers send me a 17-page letter denying everything that Gordon Ramsay Holdings said. She had worked for up to five days a week for over two years in many of his restaurants, mostly as an unpaid intern, they say, including three months at Pétrus. She’d also worked with Jason Atherton at Maze and elsewhere within the group.

The letter includes multiple pages of testimonials. In just 36 hours, Joo’s team has solicited responses from around the world. There are statements in support of her from Chantelle Nicholson, operations director for Marcus Wareing, a testimonial from Jason Atherton and later even one from Mark Askew and Simone Zanoni, two ex-head chefs of Ramsay’s flagship restaurant. All are clear: Joo had spent an awful lot of time in the kitchens of Gordon Ramsay’s restaurants. Zanoni referred to her as a true pleasure and a great asset to the team.

How much time chefs have spent working for other chefs is big stuff in the restaurant business. For example, the head chef of Heston Blumenthal’s Dinner will only give a reference to someone who has worked there for two years. But this response from both Ramsay and Joo’s people is amazing. Over the next few weeks legal letters from very expensive lawyers start flying all over London. Gordon Ramsay’s lawyers write to Judy Joo’s lawyers. Judy Joo’s lawyers write to Gordon Ramsay’s.

Meat dumplings, also known as mandoo. Photograph: Sophia Evans for the Observer

I ask Judy for a face-to-face interview. I do so a number of times, but she seems more comfortable communicating with people who charge by the hour. I sense she no longer wants to shake my hand. The lawyers accuse me of intimidating behaviour in asking all these questions and costing her a lot of money in legal expenses. They also say that in the circumstances it would be inappropriate for me to review the restaurant. The implication is that I now have a vendetta against Ms Joo, which I don’t. I simply wanted to find out why Gordon Ramsay Holdings should be so angry with her description of her time in the group.

Then in the midst of all this a less-than-enthusiastic review of Jinjuu by Fay Maschler, veteran critic for the London Evening Standard, is removed from the paper’s website. As a restaurant critic of some years’ standing, I can say that’s unusual. I am told that Joo wrote a letter of complaint about the review, which was forwarded to the Evening Standard. Will Gore, deputy managing editor of the Evening Standard, said the review had been taken down while Joo’s complaint was investigated. “I’ve now gone back to her to try and find a final resolution to the debate,” Gore said.

As I understand it, the letter is basically a long complaint that Maschler doesn’t appear to understand Korean food; that, for example, Korean fried chicken is meant to have a hard batter coating like hers does. Perhaps. It seems to me that this merely proves “authentic” really is not the same as “good”. For her part Maschler is keeping a dignified silence.

As to Jinjuu itself, it’s OK if you like that sort of thing. That said, the capital is currently rich in various takes on the many culinary traditions of Asia, including Korea, and there are better places to go. Both Smoking Goat and Flesh & Buns, for example, use similar ingredients more effectively. They also charge less for it and don’t have irritatingly written menus. Oh, and they don’t send out legal letters.

So what does this curious tale of a mediocre restaurant prove? It proves that in London’s modern restaurant business, the combination of furiously high costs, reputations and big egos can be explosive. Indeed only one thing is clear to me. Right now the people really making money out of Jinjuu are the lawyers.

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