I had to tackle this issue sometime... it's one we bakers often avoid as we peddle our delicious lemon cake as people ask 'why not an awesome chocolate cake' The truth is...no body has the recipe for the best chocolate cake ever because unless you make a cake that is just remolded chocolate in a cake shape you're never going to please the die hard chocoholics 100%. Anyone who has made it their life goal to produce a super chocolaty ultra moist cake (i.e. any baker worth their weight in superfine sugar) will agree there is always room for improvement...
The cakes I have the most success with use large proportions of dutched cocoa and oil instead of butter (hint if you're in Australia, Woolworth's homebrand is good dutched cocoa, much better than Cadburys!). There are some really good recipes out there using these principles and when studded with a few chunks of chocolate make for something really tasty even if it's not 'worlds greatest'. One of my favourite recipes (thus far in my hunt) is very simple but makes really good cake and cupcakes, I have long ago lost the link from the original but I have modified it enough to make it my own!
Ms Cupcake's favourite chocolaty moist cake
300g plain flour
400g caster sugar
150g dutch cocoa
250ml vegetable oil
250g yoghurt (plain, greek or buttermilk)
2 eggs (large free range ones please!)
1 table spoon vanilla
250ml Boiling water
Preheat oven to 160C. Mix together all ingredients except the boiling water with large spoon, then when it's all coming together add the water and beat until smooth with no lumps. You can either use this as cupcakes by pouring it and pushing some chocolate buttons into each cake or make it into a loaf or layer cake. It needs to cook for 20 mins if cupcakes and around 40-50mins for larger cakes (check after 35 mins)
As important as a great cake is an amazing toppings for your cake. I have a soft spot for sour chocolate icings so I have created one that is always a winner with my willing tasters.
Ms Cupcake's sour chocolate icing
250g cream cheese
400g icing sugar
200g dark (55-70%) chocolate, melted
3 tablespoons dutched cocoa
Have butter and cheese at room temperature and cut into small pieces. Beat the cream cheese until smooth and add small amounts of butter until a homogeneous pale consistency (usually takes at least 5 mins). Add the icing sugar in 1/4 amounts, scraping down the sides as you go, add the cocoa powder. At this point if the mixture is looking a little runny or soft place it in the freezer while you melt your chocolate to firm up. Melt chocolate slowly and don't let it heat up too much, if it does let it cool down so that when you poke your finger into it it feels like a cool bath. At this point start the mixer up again and pour in the chocolate (you might want to wear a face mask to stop all that drool from fall in ). The icing is easiest to work with when slightly soft, as it is quite firm when cold. Pipe it onto your cupcakes or smear it on and between your cakes. This needs to be eaten within a few hours or refrigerated.
Mike and his Domo-Kun cake
Another option for the 'super moist' factor is to add beetroot to your cake mix. It lends a beautiful earthy flavour not unlike that of raw cocoa and will dye your cake a brilliant pink tinged brown. I found a luscious vegan recipe here and used it along with the sour chocolate icing to make my friend a cake for his birthday recently. It was quite the decadent affair!