King Charles, Queen Camilla ‘deeply competitive’ over unique 'obsession’: book

King Charles and Queen Camilla share a hobby that has brought them closer over the years – mushroom hunting.

Tom Parker Bowles, a British food critic and the monarch’s stepson, revealed in his new book, "Cooking & the Crown," that the couple is "deeply competitive" about their hauls. He noted that wild mushrooms "are somewhat of an obsession" for the pair and they often attempt to out-forage each other.

"They call it ‘the silent hunt,’" Parker Bowles explained to Fox News Digital. "In Italy and… in a lot of places all over the world, the wild harvest of mushrooms is amazing. Up in Scotland, around the beginning of fall, you get the most amazing mushrooms. You get these… lovely, beautiful, meaty mushrooms. You get chanterelles [which are] bright yellow and scented like apricots – it just tastes so good."

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According to the monarch's stepson, Tom Parker Bowles, King Charles and Queen Camilla share a unique hobby. (Paul Ellis - WPA Pool/Getty Images)

"Wild mushrooms are somewhat of an obsession, with Charles III and Queen Camilla deeply competitive about their hauls."

— Tom Parker Bowles, author of "Cooking & the Crown."

"And we go looking," the 49-year-old shared. "The king is a great mycologist, or mushroom expert. And my mother also loves doing it. So off they go with their baskets separately, and they get quite competitive… they’re both very good. And of course, they’re always taken straight to the kitchen, and we have them with pasta."

A young Prince Charles is seen here looking at organic mushrooms during a visit to a food fair in London. (Tim Graham Photo Library via Getty Images)

According to Parker Bowles' book, there’s a "5 p.m. ritual" where everyone at the palace gathers together at a round table "after an afternoon spent outside mushroom hunting." His book features several beloved royal recipes featuring the fungi.

"The royals, since [Queen] Victoria have always used the fruits of their estates," said Parker Bowles. "They have huge kitchen gardens. They [have] herds of dairy cows for milk, cream, yogurt and butter. 

Queen Camilla and Tom Parker Bowles attend the launch of his new book "Cooking & the Crown," at The Audley Public House in London. (Dave Benett/Getty Images)

"And in the days of [King] Edward, of course, there weren’t fridges, there weren’t strawberries flown in from all over the world. You ate what was in season. And yes, the king is an expert gardener, an expert mushroom picker. He has many, many strings to his bow…. He can tell you about any mushroom. And he knows which ones are poisonous."

"Cooking & the Crown: Royal Recipes from Queen Victoria to King Charles III" by Tom Parker Bowles is available now. (Ten Speed Press)

While the king and queen are passionate about their shared hobby, they don’t exactly see eye-to-eye when it comes to their eating habits. Parker Bowles wrote that his mother, 77, likes to start her day with porridge during the winter and yogurt in the summer. For lunch, she prefers to keep things simple with a light chicken consommé or smoked salmon.

As for the king, 75, he likes dried fruit and honey for breakfast and "does not eat lunch at all."

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King Charles III and Queen Camilla cook sausages on Oct. 22, 2024, in Sydney, Australia. (Chris Jackson/Getty Images)

The Mail on Sunday recently reported that the monarch, who is battling an undisclosed form of cancer, now consumes half an avocado with "some reluctance" to keep his strength up. According to the outlet, Charles is known to rarely stop for a midday meal unless a royal engagement or official event requires it.

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The outlet noted that the king broke his habit of skipping lunch on orders from his wife, as well as his palace aides and doctors. The outlet claimed that Charles prefers to eat avocados on their own, as opposed to smashed on a piece of toast.

"At the moment, he’s obviously acting on the advice of whatever his doctors give him, so that’s not for me to comment on," Parker Bowles explained to Fox News Digital.

King Charles is battling an undisclosed form of cancer. (Hannah McKay/Pool/AFP via Getty Images)

"But he’s incredible in terms of his discipline," he shared. "The king… knows a huge amount about food… he’s championed farmers for many years… He’s a great person to talk to about food. He knows a hell of a lot more than I do."

Parker Bowles said Charles and Camilla like to keep their eating habits "simple and light" with mushrooms picked from Balmoral and cooked with pasta being "an ideal dinner."

One of Queen Camilla's go-to meals is a roast chicken. (Kin Cheung - WPA Pool/Getty Images)

"Breakfast has gotten smaller," he explained. "Lunches are now one course rather than 12. And dinner is, at a maximum, three courses… But the two things that have endured since Queen Victoria’s time are state banquets. It’s still the pomp and ceremony and glitter of gold and glasses gleaming and footmen in red coats. It doesn’t matter if it’s President Obama or the emperor of Japan… it’s soft diplomacy. It’s about putting really good food and bringing people together."

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King Charles III attends a state banquet at Schloss Bellevue presidential palace on March 29, 2023, in Berlin, Germany. (Andreas Rentz/Getty Images)

"The other thing that hasn’t changed at all is tea," he continued. "Everything stops at 5 for tea. This is a very British thing, not just the royal family. When I go for tea up in Scotland… it’s probably [paired with] a chocolate cake, a fruit cake, scones… with clotted cream and jam. 

"There are sandwiches – Hammond’s mustard sandwiches and egg sandwiches. And then there are maybe some potted shrimps, crumpets with Marmite. This is a feast unto itself… That tea is still very important."

King Charles and Queen Camilla having afternoon tea. (Tim P. Whitby - WPA Pool/Getty Images)

For afternoon tea, Parker Bowles’ book highlights a recipe for Welsh teabread, "from the kitchen of King Charles." The dish, which is made with strong Earl Grey tea, raisins and candid citrus peel, "is still popular at tea wherever he may be." For "a light supper," the couple enjoy a smoked haddock souffle.

Queen Camilla tastes some local honey during a visit to the Jersey Expo Event as part of an official visit to Jersey on July 15, 2024, in St Helier, Jersey. (Arthur Edwards - WPA Pool/Getty Images)

Parker Bowles told Fox News Digital that Camilla’s children still enjoy their mother’s homemade porridge, which she pairs with her own "delicate and mild" honey. He shared that the queen’s go-to dish for her family is "roast chicken."

"Get the best chicken you can afford, smother it with butter, put in lemon… into its cavity and season it," he said. "She has an Aga stove, which is a country thing in the U.K. It’s perfect for roasting. And then an hour later it comes burnished with crisp skin. The flesh is juicy. She uses the pan juices as a gravy."

A young Prince Charles inspects a box of wild mushrooms in Slovenia. (Tim Graham Photo Library via Getty Images)

"So many people think, ‘Oh God, British food,’" he said. "But… it’s so simple. You just need a perfect roasted chicken, asparagus with butter, some really good smoked salmon with brown bread. And there’s pudding – sticky toffee pudding. It’s hearty, no-nonsense food.

Tom Parker Bowles' new book features some recipes from the monarch and Queen Camilla, including the king's teabread. (Jane Barlow-WPA Pool/Getty Images)

"A lot of people come to the U.K. and go to rubbish pubs, have rubbish fish and chips that are soggy and dreary and disgusting and think, ‘That’s British food.’ But it’s all about the best ingredients. Not necessarily the most expensive."

A member of staff carries a tray of sandwiches during the coronation lunch organized in Downing Street and hosted by Britain's prime minister and his wife, on May 7, 2023. (Odd Andersen/AFP via Getty Images)

When it comes to eating like today’s king or queen, Parker Bowles said there’s one key rule – keep it simple. His book describes how the king’s pantry is filled with "game, beef and lamb," as well as seasonal fruits and vegetables, like "peas, strawberries, raspberries and chard."

The former Prince Charles attends a hedge-laying event at Highgrove Estate on Dec. 4, 2021, near Tetbury, Gloucestershire, England. (Peter Nicholls-WPA Pool/Getty Images)

"There is no man who knows more about food and farming, from the best of British cheeses, through rare breeds of sheep and cow, to heritage varieties of plum, apple and pear, than the king," he wrote.

"He very much practices what he preaches. The king has long talked about the importance of sustainable agriculture, and there is no waste at his table."

Stephanie Nolasco covers entertainment at Foxnews.com.