Update: made this for Will's birthday recently and used a different sized cake tin; it was about 8 inches I reckon (so quite big) and it only took 15 mins to cook. So basically watch out.
- 140g créme fraîche
- 130g very soft butter
- 230g soft light brown sugar
- 4 eggs
- 180g plain flour
- Pinch of salt
- 40g cocoa powder (or hot chocolate powder)
- 5g (1 tsp) baking powder
- 80g dark chocolate
- 130g butter, softened
- 250g icing sugar
Add the crème fraîche, butter and sugar to a bowl and mix briefly. Now add the rest of the sponge ingredients and beat together with an electric whisk until everything is well combined.
Chuck the mix into two ***small*** buttered/lined baking tins (ideally a loose bottom one so you can just lift it out) and cook for about half an hour at 180 degrees - note that if you are using a larger cake tin (over 7 inches) then it'll cook faster so I suggest putting it in for 15 mins then checking it. No-one likes a dry cake.
Check it is cooked by stabbing it with a knife (it should come out clean).
Now, to make the frosting, melt the chocolate over boiling water (bain marie). Whisk the butter and icing sugar together until light and fluffy then pop the chocolate in. Beat.
When the cake has cooled, spread the frosting liberally over the cake!
Easy. Eat. Enjoy.