The royal couple will be throwing a party for all the volunteers of charities that work hard to give the homeless a great Christmas celebration each year.
Pictured are the Duchess of Sussex, left, and Mary Berry, right, preparing to pipe icing in images release today.
Besides this, she and Prince William will be seen visiting The Passage organization, London's largest voluntary sector resource center for homeless people, helping over 1,30,000 people in crisis through its resource centre, homelessness prevention projects, and two innovative accommodation services, the Instagram post read.
The sneak peak came after the duchess stepped out in an olive-green, belted dress alongside husband Prince William to meet Tusk Awards nominees at a tea hosted by Kensington Palace last week.
The BBC said of the programme: "Throughout the programme Mary will also be cooking some of her favourite Christmas recipes for viewers to try out at home as she helps prepare the festive food for a very royal event to thank all those working and volunteering over the Christmas period".
William goes on to say that his grandmother too made her way into public service in a "man's world".
In her own one of a kind, particular way, and you know, my grandma and my granddad together are the embodiment of open help.
William is equally complimentary about his father, Prince Charles, and his late mom, Princess Diana. I obtain that you hear and also you imprint and also you be taught so mighty more by giving a tiny of your time, a tiny of your day, to correct be around'. "He has remained involved in several different organizations that help the needy".
'My mom has performed her work with homelessness and Aids and other charities and I accept as true with that I've grown up in a household which has been very mighty a case of, "Successfully, we're very lucky. You must give back"'.
Also during the special the Royals will be highlighting some of their favorite causes and charities.