Preheat the oven to 170°C (150°C Fan, Gas Mark 3). Grease 8 mini loaf tins. Put the butter in a saucepan with the sugar and treacle and place over a very low heat, stirring occasionally, until melted. Remove from the heat and stir in the milk and leave to cool for 10 minutes.

Sift the flour, Bicarbonate of Soda and spices into a bowl and make a well in the centre. Add the egg and gradually pour in the melted mixture, carefully mixing together to make a smooth, thick batter.

Divide the mixture between the tins (they should be about ⅔ full) and bake in the oven for about 25 minutes until slightly risen and just firm to the touch. Leave to cool completely in the tins then remove and wrap in baking parchment and foil. Store for 24 hours to allow flavour and sticky texture to develop.

To decorate, using a zester, take off a few strips of orange rind for decoration if liked. Finely grate 1.25ml ( ¼ tsp) of the remaining orange rind and place in a bowl. Sift the icing sugar on top. Extract the juice from the orange and add approx. 15ml (1 tbsp) juice to make a drizzling icing. Either drizzle over the cakes using a teaspoon or put in a piping bag fitted with a fine plain nozzle and pipe zig-zag lines on top of each cake. Sprinkle with orange zest if using and leave to set for a few minutes before serving.