There is a particular type of business traveller who judges a city not by its skyline or its conference centre but by what it serves for lunch.

They are the colleague who has already found the best noodle bar near the client’s office, who knows which hotel breakfast is worth getting up early for and who returns from every trip with a jar of something unpronounceable wrapped in a spare shirt.

is the professional version of that person. For more than 20 years Tom Parker Bowles has made his living eating, writing and talking about food, as restaurant critic for The Mail on Sunday, as a former food editor of Esquire, as a television judge and as the author of a shelf of books that range from British food history to royal recipes. He has also written for Condé Nast Traveller, which tells you something about how closely food and travel sit together in his world.

His second book, The Year of Eating Dangerously, published in 2007, was a travel book in all but name, a global hunt for culinary extremes that took him from water beetles in Laos to the more challenging corners of the Korean table. Two years later, Full English, his journey through the British and their food, won a Guild of Food Writers award.

It is no surprise, then, that his cooking has always been shaped by the road. And with his 2012 cookbook, Let’s Eat: Recipes From My Kitchen Notebook, now back in print, we caught up with him to talk about what he eats, where he eats it and what he carries with him when he travels.

A notebook for the road

The subtitle of the book is a clue to how he works. So does he have a favourite kind of notebook?

“I used a beautiful Florentine-style one for jotting down recipes for my book, it was a gift from the lovely [style journalist] Lucia van der Post,” he says. “I usually use Moleskine notebooks for work, especially when I’m interviewing people on the road.”

It is the practical detail that will resonate with anyone who spends their working life between airports and hotel rooms.

“The sturdy hardcover makes it easy to write anywhere, and the pocket at the back is perfect for storing receipts, menus and other bits and pieces. I have piles of them. And I take pens very seriously, especially fountain pens, which I absolutely love.”

Receipts, menus and a good pen: it is, in effect, the expense report of a restaurant critic. Plenty of road warriors have long since switched to an app for all of that, but there is something to be said for a paper notebook that never needs charging, never loses signal and can be opened on a tray table at 35,000 feet without anyone asking you to switch it to flight mode.

The taste of elsewhere

Ask a seasoned traveller what is in their kitchen cupboard and you get something close to a travel diary. Parker Bowles is no exception.

“That South African Banhoek chilli oil stuff is fantastic,” he says. “I also love Hochland cheese slices because, honestly, you can’t live without a bit of fake cheese. Shin Ramyun noodles are a favourite too, along with Buldak, the really spicy Korean ones. And of course, I always have crispy chilli oil on hand.”

There is one Caribbean import that clearly means a great deal.

“Right now, my absolute favourite hot sauce is Susie’s Original Hot Sauce from Antigua. It hasn’t been available here for a while but it’s made a comeback.”

Anyone who has ever returned from a trip and then spent months hunting for the sauce, spice mix or snack they fell for while away will understand the pleasure in that final sentence. And the admission about processed cheese is refreshing from a man who has spent two decades judging restaurants. Good taste, it seems, has room for a little guilty pleasure.

Thai food in west London

If there is one cuisine that he returns to again and again, it is Thai. His local favourites are two small restaurants in west London rather than anything with a Michelin star.

“There are two Thai restaurants I love,” he says. “One is called Fitou’s in North Kensington, it’s amazing. The chef-owner specialises in both northern and southern Thai dishes, and since I’m obsessed with authentic Thai food I appreciate how properly it’s done there.”

It is not a casual endorsement. “I even celebrated my 50th birthday at Fitou’s, and all sorts of chefs were there, they loved it too.”

The second is Thai 101 Kitchen on King Street in Hammersmith. “They also have a southern Thai chef and their food brings me so much joy. That kind of food just makes me happy.”

For a critic who could book a table almost anywhere, choosing a neighbourhood Thai for a milestone birthday says a good deal. Authenticity matters more to him than white tablecloths, and it is an approach worth copying on the road. The best meal on a business trip is rarely in the hotel restaurant, and the smartest travellers make time to eat as locals do.

Those heading to Thailand to track down the real thing should note that the rules have changed this year, with Thailand cutting its visa exemption for UK travellers to 30 days and removing business-related wording from the scheme.

The gadget question

Every food writer eventually faces the question of kitchen kit, and Parker Bowles has little patience for the gadget that has taken over British worktops.

“I couldn’t care less about air fryers but everyone else seems to think they’re amazing,” he says. “They all say they cook really fast but so do ovens. My children are obsessed with them.”

He is not, however, a purist. “I do have a small deep-fat fryer, even though it stinks the house up when you make chips, and I love a microwave, especially for making sticky rice noodles.”

His real enthusiasm is reserved for a piece of equipment many of us remember with a mixture of awe and fear from childhood.

“I’m also a huge fan of the pressure cooker. We used to be terrified of them as kids but now they’re a lot safer. You can make a stew in 25 minutes and a stock in 35. It’s witchery. Definitely one for winter.”

For anyone who gets home from a long-haul trip late on a Friday and wants something restorative without waiting three hours, it is persuasive advice. Out of season, he says, it lives in the cupboard alongside his raclette machine, fondue set and cherry pippers, a collection that sounds like the contents of an Alpine chalet.

Changing tastes

Let’s Eat was first published in 2012, and Pavilion has now reissued it in hardback. The book gathers more than 140 of the recipes he cooks at home, from comfort food classics and weeknight stir-fries to dishes inspired by his travels, such as ceviche. It also includes, rather famously, his mother Queen Camilla’s roast chicken.

So has he changed his mind about anything since?

“I still stand by many of my opinions in there,” he says. “Dover sole, for example, is still a favourite fish of mine, but it’s a real treat as it’s hard to find for less than £30.”

Anyone who has ordered it on a London expense account will know exactly what he means. His fishy horizons have broadened, too.

“I have a huge amount of time for turbot and John Dory now too. Back in 2012 I said pollock is awfully dull. I still find it slightly boring. I know it’s sustainable but I wouldn’t eat it unless I had to.”

On other matters, age has softened him. In the original book he famously banished “horrific spag bol to the culinary rubbish dump”.

“Oh God, I wrote that years ago and I’ve grown more moderate in my views as I’ve grown older,” he says. “If you want to have a spag bol, have a spag bol. It’s a very British thing, and perhaps I was being a bit harsh.”

Some things, however, remain beyond the pale. “I do think those disgusting fake meats and meat substitutes are awful, I Can’t Believe It’s Not Bacon or whatever. I hate them.”

And there is one aversion he is actively trying to overcome.

“Sadly, goat’s cheese. I want to like it and I love seeing the beautiful pyramids, cylinders and logs, which I dream of eating. I’m forcing myself to try, and I’m slowly growing to like it. But to me it just tastes like licking the farmyard floor.”

It is, perhaps, the most vivid tasting note of the interview, and a reminder that even professional eaters have their blind spots.

Thirty steaks in a day

The life of a food critic is not always as glamorous as it sounds. In Let’s Eat, he recalls once having to taste 30 steaks in a single day.

“It was for a steak competition, Farmers Weekly perhaps,” he says. “I’ve done hundreds of taste tests like that for Great Taste and so on. Eating 50 cheeses has to be the worst. I’m glad to not be doing endless tastings nowadays. Tasting 30 of anything is too much. Those days are over.”

There is a lesson there for anyone who has endured a trade show buffet or a week of back-to-back client dinners. More is rarely better, and there comes a point where even the finest food becomes a chore.

A history in a glass

These days he is as likely to be talking about drink as food. With drinks writer Henry Jeffreys he co-hosts the podcast Intoxicating History, which looks at alcohol through the ages.

“All sorts, like Roman food and drinks, which I’m fascinated by,” he says of what listeners can expect. “It’s nice to sort of natter away with someone who knows so much about booze. We’ve had some excellent guests, including the queen of the martini, Alice Lascelles.”

It follows that he has firm views on what belongs in the glass as the evenings draw in or the sun comes out.

“Well, one would have to be a martini, because that’s a perennial, obviously, but also, a real cliché, Pimm’s. When I was growing up, my dad always had the Pimm’s Vodka Cup No 6.”

His method is generous. “The key to a good one is plenty of mint from the garden, if you’re lucky enough, and lots of fruit in there too, and an extra shot of booze as well. Just to, you know, gussy it up.”

Rhubarb is another favourite, and not only for pudding. “Rhubarb vodka is very good. All you need is a bit of sugar, some vodka and a sterilised bottle and you’ve got this really nice, fruity spirit.” He is equally fond of a rhubarb crumble, “one of the very best crumbles, because it has that sweetness and sharpness, which is absolutely essential”, and rates it as a sorbet or pickled and served with smoked fish.

The classics, please

For all his adventures at the more extreme end of the global menu, his instincts at home are often reassuringly traditional. Ask what he would order from an ice cream van and there is no hesitation.

“Always a Mr Whippy cone. I sort of like ice cream, but I’m not obsessed. It has to be a really good chocolate one, like the River Café’s. Jude’s salted caramel is nice, but I tend to stick to the classics. None of those comedic flavours, please.”

It is, in its way, a neat summary of the man. He has eaten some of the strangest dishes on the planet and sat at many of its finest tables, yet what makes him happiest is often the simplest thing done properly: proper southern Thai cooking in Hammersmith, a pressure-cooked stew on a winter night, a well-made martini, a soft-serve cone on a summer afternoon.

Eating well on the road

So what can the business traveller take from Tom Parker Bowles? Carry a notebook, and a decent pen. Seek out the neighbourhood restaurant where the chef cooks the food of home rather than the hotel dining room. Bring back the hot sauce. Do not be afraid of processed cheese, and do not feel obliged to try everything on the tasting menu.

Above all, perhaps, trust your own palate. As his change of heart on spaghetti bolognese shows, food is there to be enjoyed rather than judged. And if the client dinner still has to be somewhere smarter, our guide to the best business restaurants in London will point you in the right direction.

Let’s Eat: Recipes From My Kitchen Notebook by Tom Parker Bowles is published in hardback by Pavilion Books, £26