By Amy Packham
The programme, which also features the Duke of Cambridge, sees Berry and the royal couple go on four separate visits, including to two charities they support.
The former Great British Bake Off star says about the royal couple: “They don’t just arrive and shake a few hands make a few smiles and a speech, they want to get involved, and they want to see what they can do.
“And it isn’t just one visit, they come back again and ask for the results and they remember who they spoke to last time. I think that’s remarkable.”
The one-off show sees William and Kate join Berry in the kitchen to cook some of her favourite Christmas recipes as she helps prepare food for a royal event, held to thank all those working and volunteering over the festive period.
The programme culminates in a Christmas party hosted by the royal couple – and will see former Bake Off champion Nadiya Hussain join proceedings.
A Berry Royal Christmas airs on BBC One on 16 December 16 at 8.30pm.