This Cadburys Dairy Milk chocolate cake was a chocolate cake baked in a 32m x 22cm pan. I enlarged a copy of the chocolate wrapper to fit the cake and traced over most of the lettering and Cadbury logo.
I then turned the tracing over and laid a piece of polished edge glass over the top (I would have used perspex but couldn’t find a piece small enough but you may have better luck). Using fairly stiff royal icing and a no.2 nozzle I piped over the reversed design and left to dry (the technique is called piping embossing and is described in much better detail in a book called cake decorating basics by Rachel Brown if you can find it. If you were genius at piping you could ice straight onto the cake but this technique is great for the less advanced cake maker).
I then filled 8 sections of an ice-cube tray with 230g of melted chocolate which I left to set at room temperature. When the cubes were set I emptied the tray and used it as a guide to cut away the portion of the cake where the “chunks” would sit. I then filled and covered the cake with chocolate buttercream and positioned the chunks as required.
I used approx. 750g of ready to roll fondant icing and coloured 3/4 of it with grape violet colour paste. Most of the remainder was coloured with an ivory colour paste and rolled into a rectangle wide enough to cover the top and sides of the cake. The remaining piece of white fondant was rolled out and cut to resemble the strip of white on the packaging where the Dairy Milk logo is.
When the purple fondant had been rolled I placed this on top of the ivory fondant and laid both over the cake with the double layer of fondant by the chocolate chunks. This was then folded back to look as if the packaging had been peeled back, the edges trimmed and the strip of white icing placed on top and stuck down with a little water. When this was done I smoothed over the still exposed chocolate butter icing around the chocolate chunks to give a neater appearance.
The piped embossing was pressed into the fondant while it was still soft to leave indents which were then iced into with white and purple royal icing. Finally I used gold lustre powder and dusted the ivory fondant to make it look like foil and around the edges of the purple royal icing as on the real packaging.