Burnt-Butter Brown-Sugar Cupcakes

I made these to take to an Easter Monday recital of lieder A. was giving in preparation for this weekend's Liederfest competitions; just a bunch of friends who are not afraid of giving him feedback and constructive criticism, and then enjoying some sugary cakey delights.
I've wanted to try this recipe for a while, especially as, not only do I currently have golden caster sugar in stock (it's brown caster sugar used in lots of Nigella recipes), but I also have a box of unrefined golden icing sugar! Nigella calls for this in several recipes in Domestic Goddess, but I've noticed it never appears in the American versions of the recipes, as it musn't be available there. Let me assure you, that those recipes suffer for it! Unrefined icing sugar is one of the most spectacular foodie finds I've made in the past year. The recipe for her Winter Plum Cake would not be even close to the splendour it is without this icing sugar. It's a pale brown powder that smells strongly like caramel and gives the icing a completely different flavour - gorgeously fudgey, a hint of bitterness and an aftertaste of toffee. It's not nearly as sweet and harsh as the white powdered stuff, and has a much fuller flavour. It's usually just mixed with a few spoons of water....who knew that water and sugar could taste so spectacular! I really think it is essential to bring the Plum Cake and these burnt butter cupcakes to a level that raises them to something more special.
I buy the golden unrefined icing sugar made by the UK company, Billington's. If you find it anywhere, grab it immediately!!

Anyway, I've been wanting to make this recipe for a while, and when I saw the Amateur Gourmet's post about it, that was the last straw. I had to do it now, and I had to do it the right/original way, with 2 types of golden unrefined sugars! Incidentally, I had the same problem he did with the butter not solidifying, and I ended up bunging mine in the freezer for a few minutes, which seemed to work well. In fact this recipe seems to be idiot-proof, as I chose to halve the recipe, but as I was going along, forgot to halve some of the ingredients like...erm....milk and.....ahem......baking powder. I just had really tall, fluffy cupcakes!
I found the recipe made one huge bowl of icing (and yes, I remembered to halve everything there!) which made a topping of icing as tall as the cakes were themselves! The icing itself was tooth-achingly sweet and rich on its own, but the perfect complement to the cakes, which were smoky and nutty flavoured. Decorated with some sliced pistachios and shredded coconut, these looked really pretty!

Read on for the recipe:

Burnt-Butter Brown Sugar Cupcakes
Nigella Lawson - How to be a Domestic Goddess

12 bun muffin tray lined with muffin papers

for the cupcakes:
150g butter
125g self-raising flour
60g golden caster sugar
65g light brown sugar (or muscovado)
2 large eggs
1 teaspoon vanilla extract
2-3 tablespoons milk
for the icing:
150g butter
250-300g golden icing sugar, sieved
1 teaspoon vanilla extract
2-3 tablespoons milk

Preheat oven to 200c and start burning the butter. Put butter in a small saucepan on medium heat, stirring all the time until it turns a dark golden colour. Take the pan off the heat and strain the butter into a bowl or cup, as it will have made a sediment. In other words, this is like clarified butter, but with a smoky note. Let the butter solidify again, so it remains soft for the cupcakes.
When the butter is solid, but still soft, put all the cake ingredients except the milk in a food processor and blitz to a smooth batter. As normal, add the milk down the funnel, pulsing sparingly to form a soft, dropping mixture.
Divide between the paper cases, and cook for 15-20 minutes. While the cupcakes are baking, get on with the icing. It's the same procedure for the butter - burn, sieve, solidify - then beat it with half the sieved sugar or enough to make it stiff. Add tablespoons of the milk and the remaining sugar alternately to reach a good consistency, and finally the vanilla.
While the icing's still soft, smear messily over the cooled and waiting cupcakes.