Chocolate cherry cake

I've made variations on this cake a number of times. The method for it is incredibly simple; it's all made in one saucepan! Do try it - it's difficult to go back to multiple bowls and implements after these sorts of cakes.
This a very simple chocolate cake I found in Nigella's "How to be a Domestic Goddess". It deviously appears twice; once as a full cake with orange flavouring, and once as cupcakes with cherry tastes. In both instances the flavouring is provided by adding a jar of jam to the mixture, which is not nearly as sickly sweet as you'd expect.

Almost exactly a year ago I made cupcake versions of this cake, using bottled cherries rather than the cherry jam she suggests, and on several occasions I've made the chocolate orange store-cupboard cake using jars of the very bitter grapefruit marmalade I attempted making last year (I don't mention what's in the marmalade cos I don't think "chocolate grapefruit cakes" sound terribly tempting, to be honest. I get around this labelling 'issue' by going for the generic "chocolate citrus cakes!". Seems to fool the punters sufficiently...) Seriously, this is a cake you can whip up and have in the oven in about 10 minutes, and you'll have nothing to wash up afterwards except 1 saucepan and a few spoons. Plus, it looks pretty damn fine, doesn't it? This is the first time I've managed to get my chocolate ganache absolutely perfect. That gorgeous texture that starts to run photogenically down the sides of the cake but sets just in time. Previously I've always beat the ganache too long so it turns out like cake icing or whipped cream. Still pretty, but nothing like this. I'm very happy with this attempt! :-) Let's hope it wasn't a horrible aberration.
Update 13 April: I've just changed the cooking time and ingredients for this, as I used the recipe from when I made it in cupcake form and realised I hadn't updated all sections. If you've printed it out already I suggest doing it again! So sorry!
Read on for the recipe:


Chocolate Cherry Cake
adapted from "How to be a Domestic Goddess"

Cake:
125g soft butter
100g dark chocolate, broken
300g cherry jam (good stuff with not too much sugar added)
100g sugar (Nigella uses 150g. Up to you how sweet you want it)
pinch of salt
2 large eggs, beaten
150g self-raising flour

Icing:
100g dark chocolate
100ml double cream

Preheat oven to 180c/gas mark 4
Melt the butter in a heavy-bottomed saucepan. When nearly completely melted, stir in the chocolate. Leave for a moment to begin softening, then take the pan off the heat and stir with a wooden spoon until the butter and chocolate are smooth and combined. Add the jam, sugar, salt and eggs. Stir with a wooden spoon and when is all well acombined stir in the flour. it's ok to have chunks of the jam still visible; desirable in fact!
Pour into a buttered and floured 20-22 cm loose bottomed cake tin. Bake at 180˚C oven for 45-50 minutes, until the cake has set (test with a knife or wooden stick).
Cool in the pan on a rack for 10 minutes before turning out.
When the cake is cool, break the chocolate for the icing into little pieces and add them to the cream in a saucepan. Bring to the boil, remove from the heat, let cool in the fridge for about 20 minutes, and then whisk until thick and smooth.