Preheat the oven to 180C/350F/gas mark 4
Use a 900g/2 lb loaf tin.
Grease and line the loaf tin. Cream the butter and sugar until light and fluffy. Mash the bananas and stir in. Fold in the sifted dry ingredients and milk. Pour the mixture into the prepared tin and bake for about 1 hour. Allow to stand for 10 minutes before turning on to wire rack to cool.
Caramel Icing. Melt the butter and sugar in saucepan, stirring constantly over the heat without boiling for 2 minutes. Add the sour cream and bring to the boil. Remove from heat and stir in the sifted icing sugar. Allow to cool. Spread the cold cake with icing.
