Footage from the event shows the prince get up close to the cupcakes, which included photos of himself and Kate, as well as Prince George, Princess Charlotte and Prince Louis.
"Is that me? Doesn't it look like Charlotte?" Wills asked, before Kate replied: "It looks so much like Charlotte."
When the woman who baked the cupcakes confirmed the photo was indeed Wills, he added: “Oh my goodness that looks just like Charlotte. It's incredible, I haven't seen that before.
“Very alike in similarity. Well done you that's a lot of hard work. Mary Berry would be very impressed right now. Incredible," he quipped.
William and Kate were in Bradford to conduct their first joint engagement of the year, and while there, they visited the community centre as well as City Hall in Centenary Square.
The Duke and Duchess’ recent appearance came after Wills’ Monday meeting with the Queen at Sandringham, to discuss Harry and Meghan’s decision to quit the royal family.
On Wednesday, a spokesperson for the couple insisted that Meghan was not shut out of the talks, and that she had just left the details to her husband Prince Harry.
"In the end, the Sussexes decided that it wasn't necessary for the Duchess to join," the spokesperson said.