Preheat the oven to 180C/350F/gas mark 4
Use a deep 20cm/8 inch round cake tin.
Grease the cake tin. Cream the butter and sugar in a small bowl until light and fluffy. Add the sour cream mix until combined. Gradually add the syrup and beat well. Transfer the mixture to large bowl. Stir in half the sifted dry ingredients with half the water, then the remainder. Stir until smooth. Pour into the prepared tin. Bake for about 1 hour. Stand 5 minutes before turning on to wire rack to cool. Top the cold cake with icing. Sprinkle with a little extra cinnamon.
Caramel Icing: Combine the butter and sugar in a saucepan. Stir constantly over heat without boiling until the butter is melted and the sugar dissolved. Add the milk and stir for a further 2 minutes over the heat. Transfer the mixture to small bowl. Gradually beat in the sifted icing sugar and essence.
