Place roughly cut up orange (with skin) in a food processor
Add butter and process these ingredients for a couple of seconds
Fold in remaining ingredients and process for a further 20 seconds
Pour into a well greased tin (loaf ring or circle)
Bake for 1 hour at 160°C Insert skewer and when it comes out clean remove from oven and cool cake in pan for 5 minutes. Turn onto a wire rack to cool completely.
Ice the cake when cool or you can also dust with icing sugar.
