Prince William and Kate Middleton have ordered the cakes for their wedding, which is to be held on Friday, April 29.

And it has now been revealed that William asked biscuit company McVitie’s to make his favourite chocolate biscuit cake for the celebration.

The cake is to be made to a secret royal recipe, but ingredients are said to include 1,700 crushed Rich Tea biscuits and nearly 40lb of dark chocolate.

Kate & Will wedding merchandise

Prince William in Australia & New Zealand

Paul Courtney, of McVitie’s, said: “The recipe was given to us by the Palace and we’ve been sworn to secrecy. I’d love to be able to tell you, I really would. But, it’s a royal secret.”

In addition to the chocolately treat, there will also be an official wedding cake consisting of a traditional three-tiered fruitcake by luxury cakemaker Fiona Cairns.

Kate has also been part of the designing process of the fruitcake alongside Cairns.

Fiona from Leicestershire, told the Press Association: “She has guided us right from the beginning and has quite strong ideas”.

“She knew very much what she wanted and she brought us mood boards and told us what influences she would like us to use on the cake.”

Fiona could reveal that the colours of the cake are cream and white.

It’s also thought to feature the entwined initials of William and Kate, and adorned with edible plants including an English rose, Scottish thistle, Welsh daffodil and an Irish shamrock.

“It’s a traditional cake but also quite delicate and modern. All the tiers will have a different theme,” sad Cairns.