I love this cake - really moist and with one of my favourite flavour combinations. Because I dont' have a tube pan, I've been making it in 2 8" sandwich cake pans. Works beautifully and cooks in about 25 minutes. The first time I made it I topped one half with the topping suggested in the recipe, and left the other half plain for the kids. Have to say that I wasn't desperately fussed about the recipe topping - too sweet for me - much preferred it as a plain sponge as it has so much flavour on its own. The second time I made it I put the orange liqueur in the cake mix itself (and added more orange zest). Once it was cooked and cooled I sandwiched the two halves together with a whipped-cream/cocoa/orange extract/icing sugar cake filling; then sprinkled icing sugar and orange zest on the top. Got rave reviews!
Since my husband doesn't like chocolate I'm going to try it next time using a coffee and almond/amaretto combination.
A year later, and it's our staple base cake mix - I've made it lots of times as a coffee cake, mocha cake, chocolate cake, and got rave reviews for a lemon version with a lemon-creamcheese frosting found elsewhere on this site.