Chocolate Orange Syrup Loaf Cake Recipe

I am a big fan of Nigella Lawson's no nonsense if sometimes a little over-indulgent attitude to cooking. Her 'How to be a Domestic Goddess' is my go-to book when I am looking for something yummy to bake just for the hell of it, and the Lemon Syrup Loaf cake is a definite favourite in our house!
Sometimes, however, only chocolate will do so a few weeks back I had a play with the Lemon Syrup Loaf recipe and came up with a gorgeous chocolate orange version...