If I want a special cake, I use a choc cake recipe I developed myself - rather than a 2 egg, 60, 60, 60 cake with self-raising flour I do 2 eggs, 60, 60, 60 g plain flour + 2tsp baking powder + 60g melted plain chocolate. ie equal weights of everything. The chocolate is added after mixing the butter/castor sugar and adding the egg yolks only.
I separate the eggs, whisk the whites with cream of tartar and fold in with the flour/baking powder. This cooks in a 10" x 7" tin - enough for 2 layers.
It's then sandwiched with a whipped cream layer, and a truffle fruit layer - ~200/250g of good plain choc with a good slosh - less than 60mls of double/whipping cream whipped until just about milk chocolate colour. To this I generally add raspberries soaked in Cointreau, or blackcurrant with cassis - any combination would work just as well as long as it went with chocolate. This makes the fourth layer.
It's best 'assembled' in something resembling a straight-sided loaf tin - a silicone one would work well - I have one that 'bolts' together at the corners, with a removable base that slides out but the cake often breaks when placing in the base. It's a professional one, but not sure that it's best for the job. The other method is to increase the cake to 3 eggs and use a modern rectangular tin for a 2lb loaf and slice into 3 taking out the middle slice so it fits. However, in a tin that size it tends to crack on the top, so you don't have a 'good' slice for the top.
It's then iced with the choc icing from Larousse Gastronomique. ie plain choc/butter in the proportions of 150g choc to 65g unsalted butter. These are melted together over a bowl of hot water, stirred well, allowed to cool, and then either poured over the cake - need a tray to catch drips to re-pour, or whipped with a balloon whisk until milk choc colour but not too much, when it can be spread like a frosting. You can then roll the sides in grated white chocolate etc chopped nuts and leave the tops plain etc. Hides slightly dodgy plastering - very forgiving really.
Can be cut into slices and frozen individually, so you can eat just 1 slice at a time if you don't want too much. Or even half a slice.
Must post in recipes one of these days - it's been on mumsnet loads of time.