Buttermilk Birthday Cake

Of course, you can make birthday cake simply enough by following the Victoria sponge recipe, and I often do just that. But this is one of my most ecstatic discoveries: a cake that holds its shape whatever mould you want to cook it in, that can bear the weight of as much icing as you want to drape it with and is, after all that, the best-tasting birthday cake you will ever come across. Not, of course, that is has to be a birthday cake. My children like