Trying to bake a chocolate cake

As I have said before, I am not a baker. But with two guests who love chocolate cake, when I found what looked like a me-proof recipe, I thought I'd have a go.
       The recipe came via a friend's food blog, Capital Living, and she got it via Annabelle White, who calls it "Lady Glenorchy's Super Simple Chocolate Cake". It really did look easy. You just put all the ingredients into the food processor in the order given, whizz for one minute, then pour into the prepared tin and bake.
        Now that's my kind of cake recipe. But I should have paid attention to the "Cook's Tip" at the bottom:
"Slice this un-iced cake in half and freeze one part and keep the other for immediate use." Because (as I should have known from the list of ingredients) this makes a pretty big cake. So big, in fact, that it only just fitted into my reasonably large processor. And when I poured it into my carefully prepared tin, it came almost up to the top. Oh dear, I thought. Not good.

By then it was too late to do anything but bake it. I knew the oven would work best for a big cake like this on "bake", no fan, but I think I should have also set the temperature slightly lower - I'm pretty sure this oven tends to be a little hotter than the dial says. When I checked, the cake was looming up alarmingly in the tin and starting to plop gently over the edge on one side and down onto the bottom of the oven. Not a pretty sight. 
          I turned the temperature down 5 degrees and left it in until it was cooked through. Once it was cool, I eased it gently out of the tin. It looked rather splendid, a great high domed creation,  a bit of a crest on top but beautifully smooth all round - except for the crumbly bit where it had plopped over and hadn't come out quite cleanly.
          Icing covers a multitude of baking sins. I was determined to do this properly, so I found a good ganache recipe I'd cut out of the paper years ago, from Clark's Cafe in Wellington's wonderful central library. I'd never actually made it before, but it looked very simple too. The recipe says "chocolate buttons", but I used Whittaker's Dark Ghana 72%, so I microwaved it first to make up for it melting less easily than the buttons would.          

          It was the best chocolate icing I've ever made. There was just one problem: after I'd covered my very tall cake thickly in a casual rustic way, filling in the little crater on one side, I had quite a bit left over. Whipping it with extra cream produced a very nice filling. I needed this, given the impressive height of the cake. It was just a pity I hadn't thought to cut the cake in half through the middle and fill it before I iced it...Still, serving the filling alongside the slice meant you got more. My guests didn't complain. 

          While the cake was good, it seemed to settle and taste even better next day. Next time, I'll get it right. I reckon that for most purposes the recipe would be better halved, and the icing would work neatly with 250ml cream (from a 300ml bottle) and 250g chocolate (the weight of one large Whittaker's block). You might still have some left over, but I'm sure you could cope creatively with that.

Lady Glenorchy's Super Simple Smaller Chocolate Cake
1 cup white sugar

1 egg

1/2 cup plain yoghurt

1/4 cup cocoa and 1/8 cup cocoa (halving 3/4 is a bit tricky, but this will work)

100g melted butter

1 tsp baking soda

just under 1 tsp vanilla (well, 3/4 tsp, but I don't think the tiny bit more would matter)

1/8 tsp salt

1 and 1/2 cups self-raising flour

1/2 cup boiling strong coffee

Set oven to 160C.

Grease sides of a 23cm round loose-bottomed cake tin and line base with baking paper [Capital Living's useful instruction]. 

Place all the ingredients, in the order given, into food processor bowl.  Process for 1 minute.

Bake at 160C for approximately 45 minutes (it might take a little longer, depending on your oven). 

Cake is cooked when a skewer in the middle comes out clean.

Cool in tin before removing and ice with your favourite chocolate icing.

Clark's Even Better Chocolate Ganache
250 ml cream
250 ml Whittaker's Dark Ghana 72% chocolate

Break chocolate into pieces, put in large glass jug, and microwave on low until just starting to soften. 
In a small saucepan, bring the cream just to the point of boiling.
Pour it over the chocolate and stir until smooth. 
[You need to keep stirring for quite a while - at first the mixture looks pale and unappetising, but the longer you stir, the more it darkens.] 

The advice that came with this recipe was excellent. Of course if I'd read it earlier, I would have made the icing before I made the cake.
"If you serve this while it is warm, it is the best chocolate sauce. If you leave it for a few hours [2 hours seemed to be enough], it becomes spreadable and this is when you ice the cake.  When it is at the spreadable stage, if you whisk it, it becomes an airy chocolate filling. If you leave it overnight it will become hard. To soften it again, chop into pieces, slightly warm and stir to combine."