All aboard the gastronomic express: The Royal Scotsman's kitchen has been manned by some of Scotland's best chefs

It was little more than an egg in a cheap floury roll, but it counts as one of my best meals ever. The aperitif was a 25-year-old Islay malt whisky and the dessert course came from a bag of jaw-breaking Soor Ploom sweeties. The ever-changing view was from the engine cab of the Royal Scotsman luxury train: buzzards soaring above deer on heather-clad hills, lochs and waterfalls, and a necklace of islands glistening in the distant Inner Hebrides.

Best of all, though, was the egg – laid that day and fried on the blade of a coal shovel, red hot from the firebox, as the train wound through glens and mountains towards Scotland's west coast. Onboard was the young head chef Andrew Fairlie who, two decades later, became the only holder of two Michelin stars north of the Border, for his eponymous restaurant at Gleneagles hotel.

He says: "It only goes to show that while food is the most important element in any restaurant, it is not the be-all and end-all. Atmosphere is essential, too. At Gleneagles, we've got one of the world's finest golf courses on our doorstep, and on the Royal Scotsman train the magnificent scenery changes every minute. I love the mountains, especially." Fairlie, now 48, spent two seasons on the Royal Scotsman, despite an inauspicious start. "In my second week, the train set off without me at Fort William and no one noticed. It took a two-hour taxi chase to catch up with the train." When not at the stove, Fairlie, 49, is a keen hill-walker. He has climbed Mount Kilimanjaro and bagged almost 40 Munros, Scotland's mountains over 3,000 feet.

His predecessor on the Royal Scotsman, Andrew Radford, 55, is also a Munro-bagger, almost 60 so far. "The main advantage, enjoyed by no other restaurant," says Radford, "is that we travelled to our suppliers, not the other way round. We could buy the best ingredients as we went: seafood caught that day and game fresh from the moor."

Radford's latest enterprise, the 90-seater Timberyard, with elder son Ben picking up the apron strings in the kitchen, was Edinburgh's hottest restaurant opening last year. The tables and the borders of his on-site kitchen garden are fashioned from recycled wooden railway sleepers that Radford bought from a scrapyard when he was head chef on the train. "During an excursion, while passengers visited a castle, a whisky distillery or the gardens of a stately home, I'd forage in the countryside for bitter cress, wild garlic and leeks to add to a dish that evening."

Following Radford and Fairlie several years later, in 2002/03, was Craig Wood, who has won plaudits, including a Michelin recommendation, for his Wee Restaurant in North Queensferry, Fife. In the shadow of the Forth Railway Bridge, this triumph of Victorian engineering is a constant reminder of Wood's time on the Royal Scotsman. So what is it about cooking on a train that inspires young chefs and hones their skills?

Wood, 40, says: "The galley kitchen measures only about six metres long. There is a narrow passage, scarcely a half-metre wide, between six burners, stoves and workspace on one side and fridges and a sink on the other. You quickly learn how to be efficient at ordering supplies, planning menus – and improvising.

"Once, arriving late at the railhead on Kyle of Lochalsh pier on the west coast, we had to make a quick turnaround before serving lunch – and the fridge was bare. I called our local fisherman Neil McRae on his mobile. He was out on his boat. He drew alongside the pier, jumped onto the train with a sack of hand-dived scallops and within minutes he was helping us open them. We served them with a wild leek butter sauce. His wife had to drive to pick him up a few stops down the line. You don't get shellfish fresher than that.

"Neil was also fiddler in the ceilidh band entertaining passengers on Tuesday nights. The deal was that they played for as long as there was whisky. More than once our travellers spilled out onto the pier and were still dancing reels as the sun came up."

Cooking in the tiny galley kitchen, where current head chef Mark Tamburrini, 39, is now in his fourth season, poses challenges. "My first month was the hardest work I've ever done, but you learn quickly." he says. "Beware the emergency stop –possibly Highland cattle on the line. It happened once when we were about to serve lemon posset. They went flying everywhere. One menu had a choice of three starters, but the 36 on that trip had different likes and dislikes, as well as dietary requirements, so I ended up making 16 different starters. Royal Scotsman guests expect service like that."

Don't serve soup while on the move is a golden rule. The train is prone to shoogle, a Scottish word meaning to shake or wobble. But a perfect panna cotta, the Italian dessert which Tamburrini flavours with whisky, should be capable of a distinct tremble. So a Royal Scotsman shoogle adds a theatrical bonus.

Travelling on this luxury train requires deep pockets. "But for our dollar you get the best scenery you could wish for, and it certainly gets you in the mood for dinner," said one American in the observation car on my journey more than quarter of a century ago. As we responded to the magic words "Last call for dinner!" he added: "God may have spent six days organising the world, but on the seventh day he must have decided that small was beautiful and chose to play at trains in Scotland."

Acrobatic waiters slalomed between passengers in evening dress and kilts in the two dining cars. Fairlie conjured up fresh asparagus with Beluga caviar, calves' sweetbreads with sherry, local seafood including salmon, halibut, langoustine and turbot with a saffron beurre blanc, Aberdeen Angus beef with wild mushroom sauce, and home-made ice-cream. This did not stop me having porridge and kedgeree for breakfast.

Steam power no longer features on the Royal Scotsman journey, and anyway health and safety regulations today would not allow passengers to fry an egg on a shovel. But Scotland's scenery is timeless, and the choo-choo chefs continue to work magic with the finest Scotland has to offer from sea, sky, field and moor.

The Royal Scotsman season runs from 21 April until mid-October. The four-night Classic Journey costs £4,330. royalscotsman.com

Mark Tamburrini's whisky panna cotta

1 pint of double cream
Quarter of a pint of milk
100g of caster sugar
2 sheets of gelatine
1 vanilla pod
1 measure of whisky

Add milk, cream, sugar, whisky and the vanilla to a large pan and bring to the boil. Stir well to dissolve the sugar. Soak the gelatine in cold water until soft then squeeze out the excess water and dissolve in the cream mixture.

Pass through a fine sieve and into a bowl. Chill by placing the bowl in cold water until nearly set.

Fill moulds with the mixture and cover with cling film. Place in fridge to set for 3 to 4 hours.

To plate, dip the panna cotta moulds into a bowl of warm water for about 8 to 10 seconds to release. Do not leave in the water long enough to melt. Turn on to plates. Serve with raspberry sorbet and oatmeal tuiles.