The 86-year-old is a fan-favourite of Prince Louis, who was said to be “obsessed” with the baker.
The young royal, now two, was said to “whoop and clap” whenever he saw Dame Mary on TV and in cookbooks.
Prince Louis also developed a taste for her Very Chocolate Cake, Plum Crumble and fruit scones, according to a royal insider.
Last year they told The Sun, the youngster “likes nothing better than to check on Mary Berry cookbooks” and recipes.
They claimed Louis “loved the pictures” and “points out all the things he wants to eat”.
The unnamed source added: “Whenever he sees Mary on the television, he whoops and claps his hands.”
This followed the Duchess of Cambridge’s admission that one of Louis’ first words was “Mary” after he regularly spotted her cookbooks in the kitchen.
Dame Mary has also spoken out in support of the Royal Family a number of times including when she praised Kate and Prince William.
JUST IN: Kate and William defended by Mary Berry before Harry’s ‘way off’ claim
Dame Mary noted they would “come back again” and “ask for the results”.
The veteran chef also made comments about Meghan and Harry’s decision to leave the Firm last year.
During an appearance on Lorraine, the Scottish presenter admitted she was “delighted” to have Dame Marry “here all morning with us”.
She turned to the star and asked: “Mary – Harry and Megan is the big story this morning, it’s just a bit sad isn’t it?”
Dame Mary replied: “I just feel it’s very sad.”
The chef then nodded sympathetically as she clenched her lips tightly together.
Dame Mary referenced her closeness to the Royal Family before explaining more about the situation.
She continued: “They are just like you and me.”
Dame Mary seemed to support Meghan and Harry’s decision when she noted that “they love each other” and would try to help the nation.
She added: “[They] want to do everything they can for the country, I promise you.”
At the time, the Sussexes’ statement explained that they intended to “step back” from the Firm and “work to become financially independent”.
They wanted to do so “while continuing to fully support Her Majesty The Queen”.
Lorraine felt it was “a real shame” that Meghan and Harry were leaving because “they were so good at what they were doing”.
She added: “It’s all just gone horribly wrong but clearly they’re very unhappy and miserable, which is a shame.”
Since their departure, the Sussexes have spoken out about the pressures of being in the public and media spotlight.
During their interview with Oprah Winfrey earlier this month they claimed a number of issues and Meghan’s mental health struggles led them to leave.
The claims during their tell-all chat have caused issues for the Royal Family who will investigate the Duchess’ claims.
Mary Berry Everyday airs at 7pm tonight on BBC Two.