so quite traditional, but with a modern twist. reporter: the wedding cake will be a classic design. no color, just cream and white, with carefully considered floral decorations. each with a meaning. i ve been learning very much from her that she has selected these flowers. so, for example, the bridal rose symbolizes happiness. the oak and acorn symbolize strength and endurance. we have a long list. a lot of these are actually within the architecture of buckingham palace. and sweet william. we haven t made sweet william yet, but we will be. reporter: william has actually been working on his own cake, as well. in a break from tradition at buckingham palace, he s going to have a groom s cake. guess what? it s made of chocolate cookies. the rich tea biscuits, mixed