Cakes always look better when they are decorated, even if it is with a simple "happy birthday" messaged piped across the top with some sugar gel. Sprinkles are a good option, introducing color and a sense of festivity, but for a more grown-up look, chocolate shavings are the way to go. For example, the black and white cake made by Anita, from Dessert First, only needed a few shavings to turn into a "wow" dessert. Not only are they beautiful, but the shavings are no more difficult to produce than shaking sprinkles from a little container. To make them, all you have to do is (carefully) run a potato/vegetable peeler over the edge of a chunk of chocolate, allowing the "peel" to fall onto the cake. It helps to use cold chocolate, so it will shave cleanly and not get stuck in the peeler.