We love hearing about all the dos and don'ts of mealtimes at the palace, and this unexpected royal rule has really sent our heads spinning.
Did you know that point-edged food is not allowed at the Queen's table, as part of a tradition started by her royal ancestors?
WATCH: The Queen's daily diet
According to the monarch's former royal chef Graham Newbould, during his time working for Her Majesty, she never ate sandwiches shaped with points. The Queen is instead served small 'jam penny' sandwiches at afternoon tea.
In the documentary Secrets of the Royal Kitchen, Graham revealed: "The royals never have square sandwiches because tradition has it that anyone presenting them with pointed-edged food is trying to overthrow the throne of England."
Wow, we did not know that!
The Queen prefers round sandwiches at tea
There's also another theory as to why the Queen prefers round sandwiches, which dates back to Queen Victoria's reign. Apparently, her husband Prince Albert thought it unlucky to eat coffin-shaped food!
Another former royal chef, Darren McGrady – who cooked for the Queen for 11 years - previously discussed the Queen's eating habits during a Q&A in a YouTube video.
One of his followers asked: "The Queen always eats fancy/expensive food. Are there any simple cheap foods she liked?"
"The Queen doesn't eat fancy rich foods all the time, nobody can!" Darren responded. "It's only when she's entertaining guests that the Queen has a banquet with lobster and caviar and things like that, but the rest of the time it's just healthy eating – a little bit of grilled fish with some salad.
Former royal chef Darren McGrady shows how to make Jam Pennies
"One of her favourites is Jam Pennies, they're just bread and jam," he continued, pointing to a picture of small, round disks of white bread with a layer of strawberry jam in the middle."
The royal chef elaborated on the Queen's sandwich preferences during an exclusive interview with Coffee Friend, saying: "We'd choose the sandwiches that were served. They varied, they could be the traditional cucumber sandwiches, but depending on the different houses we travelled to - take Balmoral for instance, we'd have so much salmon coming in, we'd have that fresh salmon and make a beautiful salmon salad or put that into the sandwiches. At Balmoral, the Queen would go and pick berries from the gardens, bring them back to the kitchen and we'd serve some for dinner in the evening and I'd get to make jams and jellies that would last all for the year."
Cue children now getting round sandwiches in their lunchboxes...
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