"Christmas cake?" suggested Mr. Fixit. "You hate fruitcake," I said. "That's not Christmas cake," he said. "Yes it is," I said. "Christmas cake is, like, chocolate cake with icing," he said.
Oh. Well, I could do that. And then a little "where's that recipe" buzzer went off in my head, something we'd made once or twice but not for a long time, something I knew we had most of the ingredients for, including a jar of marmalade that The Apprentice had brought with her this week...aha. I had somehow lost or purged the magazine page in my binder, but found it online. Baker's Chocolate Mandarin Orange Cake. It's not exactly a diet recipe, but the cake itself isn't huge (good for our smallish family), and you can cut small pieces.
Sorry there are no photos there, but if I remember, I will get one of our cake when we make it.