Another birthday cake

Another year, another surprisingly definite order from the child who generally knows his mind and sticks to it.
The only thing I was unsure about was what exactly 'carving' a five into the top of the cake meant, but apparently my solution of (wait for it...) making up a paper template and filling that space with hundreds and thousands pressed into the icing was perfect. Older brother helped with m&m placement, which I was happy to delegate.
The icing was not what I imagined - adding some melted chocolate to a butter icing base resulted in a bit of a ho hum brown. not the rich glossy dark brown I wanted (like Mrs Commings' cakes).