Queen Camilla raised two children with her ex-husband Andrew Parker Bowles before being thrust into the public eye following her marriage to King Charles.
Just like the royals, Camilla ensured she kept her home life with Tom and Laura private, but her son has lifted the lid on their "strict" diet behind closed doors.
"We grew up eating locally, seasonally and organically, way before they became the overused buzzwords they are today – my mother shopped in the butcher, fishmonger, bakery and greengrocer," food critic Tom explained in an interview with You magazine.
While they did indulge in some processed foods, Tom admitted they were kept to a minimum in his household. His mother was a "good cook" who preferred home-grown ingredients.
"But when Sainsbury’s opened in Chippenham at the start of the 80s it was like that moment in The Wizard of Oz where it moves from monochrome to technicolour.
"Ice Magic! Birds Eye Chicken Pies! Butterscotch Angel Delight and huge variety packs of Monster Munch! We wanted it all, although my mother was fairly strict in what we were allowed," he continued.
Cooking and the Crown author Tom added that some of Queen Camilla's staple dishes were scrambled eggs for breakfast and shepherd's pie or roast chicken for dinner.
The family would eat "peas from the garden, strawberries from the garden" at his childhood home, Bolehyde Manor in Wiltshire. Camilla lived at the 8,000-acre manor house from 1973 to 1986, making Tom 12 when he left the property.
Camilla's healthy food choices are similar to King Charles and her step-grandchildren Prince George, Princess Charlotte and Prince Louis.
Royal diet
On a school visit to Slough, Camilla previously told students: "I tell you what I really like – eating peas straight from the garden. If you take them straight from the pod they are delicious and really sweet.
"I take all my grandchildren down to the garden and they spend hours and hours eating peas."
However, Tom admitted that he developed a sweet tooth and was guilty of raiding a master's sweet drawer at his prep school, Summer Fields in Oxford. So it's possible that Camilla's five grandchildren – Tom's kids Lola, 16, and Freddy, 14, and Laura Lopes' children Eliza, 16, and 14-year-old twins, Louis and Gus – follow a more relaxed diet.
Meanwhile, King Charles is known to champion a sustainable diet, even gardening and eating hearty meals made using produce from his own estate.
Gushing about his stepfather, Tom said: "His Majesty The King is a true food hero. There is nothing he doesn’t know about rare breeds of cattle, heritage varieties of plum and apple, the joys of mutton and wild mushrooms, and the oozing allure of a stinky cheese.
"Every monarch has had their own tastes and preferences, and the King’s interest in sustainable, regenerative farming is well known, and was way ahead of its time. His advice is invaluable, his knowledge profound."
He also hates food waste, Tom revealed, adding that leftovers will be reused the following day. "Nothing’s allowed to be thrown out."
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