Awesome chocolate sponge birthday cake

This is my classic, fail-proof and always popular chocolate birthday cake, and it's survived being carried in the tube to Ealing, and on the overground to Barnsbury, and once all the way to Gloucester for my Aunt's 60th. I make this for nearly every single birthday - the beauty of the icing means that even if your sponge turns out terribly crumbly or dry, it will still be a hit. That said, this sponge is easy-peasy, slightly dense, and has been given the thumbs up by so many of my friends I've lost count.
I found this recipe in a now-unknown website place way back when I was first a student in London, to make for my flatmate on his birthday and I just kept going back to it. It's the creamy Philadelphia icing which does it, pushing it over into that amazing cheese-cakey flavour territory.
I've made this particular batch as cupcakes, as taking a birthday cake to a pub can be quite messy, and make the bar staff hate you. We enjoyed these in the Southampton Arms off Highgate Road, and it is a brilliant pub.

Makes 12 cupcakes. Maybe 13 but  who has a 13-case cupcake tray?
Awesome chocolate sponge birthday cake (in cupcake form)  

• 175g unsalted butter, room temperature
• 175g caster sugar
• 30g cocoa
• 150g self-raising flour
• 3 eggs
• 1 tsp vanilla extract 

Preheat the oven to 180C, and crack your three eggs into a smallish bowl. I like to use a jug or something, anything that my electric hand-held beaters can sit in. Add the vanilla to the eggs, and mix until frothy and pale.

Give the beaters a quick rinse, chop your butter up into a few small chunks and throw into a nice-sized mixing bowl, and combine the caster sugar and butter for a fair amount of time until mixed together. This usually takes a bit longer than I expect it to every time, but eventually it will come together in a nice consistent mixture. 

Slowly drizzle the eggs into the butter and sugar, a bit at a time, stirring all the while until it's all combined nicely. Now the messy part: measure out your 150g of flour and your 30g of cocoa (I normally make up 180g) and put it into a sieve. Hold it nice and high up above the bowl and gently tap it down - it does go a little bit everywhere, but the more air in it the better. Then fold in! Yummy chocolate batter.
Put them in the oven - I normally spread the batter thinly between two cake trays and make sure its greased and lined - and check frequently. Sometimes this cake only takes 10 minutes, so check crazy often! When a skewer is coming out clean, take the cakes out.
Meanwhile, you can start on your icing while the cakes are baking.

Rich cream-cheesey chocolate icing

• 70g unsalted butter, room temperature (the remaining bit of your 250g pack from pack used in the cake)
• 70g cream cheese 
• 225g icing sugar
• 1 tsp vanilla extract
• 4 tsp cocoa, sifted

Mix together your unsalted butter with the cream cheese and the vanilla until blended, using the hand-held mixer again. This might end up smeared up the sides of your bowl, so just scrape it down. Then carefully sift in the icing sugar and cocoa. This can make a HUGE mess if you use the hand-held mixer, so maybe mix through half using a wooden spoon, then the remainder.

Then try not to eat it with your hands. I know it's a challenge for me.

Wait for your cake to cool (crucial step or your icing will melt and look tragic), and if you're doing cupcakes, smear liberally on top, otherwise coat the top of the lower sandwich half, place the second sandwich half on top, then cover the whole lot in icing. And if you're feeling fancy, sprinkles or whatever you feel like - it's a basic chocolate cake so you can spruce it up a little.

 I guarantee you will be very popular indeed!