Preheat the oven to 180'C.
Place cupcake cases into silicone or tin moulds.
Split the vanilla pod in half and scrape out the seeds.
Whisk together the butter, sugar, and vanilla seeds until light and creamy. Add one egg at a time and combine well. Sift the flour and the baking powder into the mixture and gently fold together. Spoon the mixture into the cupcake cakes, transfer to the oven and bake for 12 to 14 minutes.
Remove from the oven and leave to cool before icing.
Sift the icing sugar into a bowl, add the butter and beat together until pale and fluffy.
Place the mixture into a piping bag with a star nozzle and pipe on to the cakes once cool.
«When piping, always start from the edges and work your way in.»