The Prince of Wales was among the famous faces to send well-wishes to Dame Mary Berry on her milestone birthday on Monday.
Prince William, 42, called the TV cook, a "national treasure" as he joked he "dreads to think" who will be baking her a birthday cake.
Dame Mary celebrated her 90th birthday on 24 March, and her "extraordinary life and career" will also be celebrated during a special episode of BBC’s The One Show on Monday.
In a message played on Scott Mills' BBC Radio 2 breakfast show, William said: "Hi Mary. I want to wish you a very happy 90th birthday.
"You are a true national treasure and we've loved working with you over the years. Have a fantastic day today.
"I dread to think who’s cooking your cake and the criticism they might get, but good luck and I hope it goes really well."
Watch Mary's reaction below...
The Prince and Princess of Wales have met the Queen of Baking on a number of occasions over the years.
Kate was joined by Dame Mary at the Back to Nature festival at RHS Wisley in September 2019, with the pair arriving together on a tractor before icing cupcakes.
William and Kate then joined the TV icon for A Berry Royal Christmas on BBC One in 2019, where they went head-to-head as they made a festive roulade. Dame Mary diplomatically refused to choose a winner and declared that their creations were equally delicious.
And when the royal couple tried their hand at making Welsh cakes in Pontypridd in February, William said of his baking skill: "Mary Berry taught me everything I need to know."
The video message will also be shown on The One Show in the special episode as presenters Alex Jones and Roman Kemp speak to Dame Mary about her life and career.
William's birthday message comes just ahead of the children's Easter holidays from school.
Meanwhile, The One Show will also feature celebrity guests including The Traitors presenter Claudia Winkleman, as well as former The Great British Bake Off presenters Mel Giedroyc and Sue Perkins.
Dame Mary left Bake Off in 2016 when the series moved from the BBC to Channel 4.
She has written more than 80 cookery books, becoming a UK household name for her recipes and tips, and was made a Dame Commander by the Prince of Wales in 2021 for a lifetime of cooking, writing and baking.