Cream the butter in a bowl and then beat in the sugar.
Beat in the eggs, egg yolk and vanilla essence.
In a separate bowl, mix together the flour, baking powder and salt.
Combine the two mixtures.
Mix in the cinnamon and cappuccino.
Place in to cupcake cases and bake for 20 minutes at 350ËšF. Leave to cool and then decorate with glace icing and a sprinkling of cocoa powder.