What's more, Rayder explained that large containers of British foods are taken on trips during her royal tours in case the quality of local food was not satisfactory.
"If there is still a question mark over the quality of the local food, large containers of nourishing British foodstuffs will be taken on the trip, and bottled water in case the local supply proves unreliable.
"Hotel staff will also be told in advance how the Queen likes her chosen tipple, Dubonnet and gin – an exact 50/50 mix, usually taken at 6 pm, in a tumbler.
While her favourite food remains unknown, her former royal chef Darren McGrady (who worked at Buckingham Palace for 11 years followed by Kensington Palace for four) revealed that the Queen loves dessert.
In fact, the chef said the monarch cannot resist chocolate biscuit cake.
"Now the chocolate biscuit cake is the only cake that goes back again and again and again every day until it’s all gone. She is absolutely a chocoholic," he told Hello.
The Queen is said to love the cake so much that she has it daily, and refuses to leave home without it.
However, she is also said to enjoy fresh fruits and salad.
"With a banana, she’ll cut off the bottoms and cut the banana lengthwise, and then cut the banana into tiny slices to eat it with a fork," McGrady said.
The Queen also prefers her meat cooked well done.
"For the main course she loved game, things like Gaelic steak, fillet steak with a mushroom whisky sauce, especially if we did it with venison," the former personal chef said.
"For a first course, she loved the Gleneagles pâté, which is smoked salmon, trout and mackerel.
"She loved using ingredients off the estate and so if we had salmon from Balmoral from the River Dee, she’d have that, it was one of her favourites.
"We used a repertoire of dishes, mainly British and French food.
"We cooked a lot of traditional French food like halibut on a bed of spinach with a Morney sauce."
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He considered how "amazing" it would be to work in the royal kitchens, and a few weeks later he visited Buckingham Palace for an interview and secured a job as a personal chef to the Queen.
However, Darren concedes that the Queen never was a foodie.
"She always ate to live rather than live to eat," he said.
"Prince Philip was the foodie. He'd want to try any new dishes all the time and got excited about new ingredients whereas the Queen, if we had a new recipe, she'd have to look at the whole recipe before saying, 'Yes ok let's try it'. But for the most part she stuck to the same dishes week in week out," he added.
Furthermore, the Queen - who shares four children with her husband, Prince Philip - enjoys particular foods for different occasions.
The former chef listed some of the meals that members of the royal family enjoyed when they visited her for afternoon tea.
"If she was having dinner with Prince Andrew, his favourite was crème brulee with Sandringham oranges," Darren said.
"It's like any mum with a son or grandson coming home. If Prince William was coming for tea it would be a chocolate biscuit cake. He loved those."
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