Pre heat the oven to 180 C / Gas 4. Grease and flour a cake tin.
Cream the butter with the caster sugar. Beat together your eggs and pour the eggs into your butter mixture and beat well. Stir in the peppermint extract, then fold in the flour. Tip into the prepared tin.
Bake cake for 20 to 25 minutes or until golden and firm to the touch.
For the icing, cream butter and gradually add the icing sugar whilst mixing. Stir in the peppermint extract.
Once the cake is cool, cut out the middle of your baked sponge to create a POLO® shape. Then smother the cake with your buttercream.