Primrose Bakery Chocolate and Banana cupcakes

I needed an excuse to use my new and very apt cake stand that my mum's friend kindly bought for me. The usual overripe bananas in the fruit bowl and a desire for cupcakes, led to these mammoth sized cupcakes from the Primrose Bakery cookbook. 

Ingredients

Makes 12

125g unsalted butter, at room temperature
250g caster sugar
2 eggs, lightly beaten
1 tsp good quality vanilla extract
250g plain flour, sifted
2 tsp baking powder
4 ripe bananas, mashed with a fork 175g good quality dark chocolate (70% cocoa solids), broken or chopped into small pieces

For the chocolate icing;

4 tbsp cold water

28g cocoa powder

125g butter melted

284g icing sugar

Preheat the oven to 180ºC and line a 12-hole muffin tray with the appropriate size cupcakes cases.
In a large mixing bowl, cream the butter and sugar until the mixture is pale and smooth, which should take 3-5 min using an electric mixer.
Add the eggs and vanilla extract and beat again briefly (add the eggs one at time making sure they have incorporated well in between). Add the flour and baking powder and beat again until well combined. Stir in the mashed bananas and chocolate pieces using a wooden spoon (careful not to over-stir).
Carefully spoon the mixture into the cupcake cases, filling them to about 2/3 full. Bake in the oven for about 25 minutes. To check they are cooked, insert a skewer in the centre of one of the cakes - it chould come out clean.
Remove from the oven and leave the cakes in their tins for about 10 minutes before placing on a wire rack to cool. Once they are completely cool, ice the cupcakes with chocolate buttercream. If you wish, pop some chopped walnuts on each one. Alternatively, you could simply serve them with no icing at all for a breakfast treat, warmed in a the oven for a few minutes beforehand. 

For the chocolate icing;

Melt the butter with the water in the microwave. Mix with the icing sugar and cocoa until smooth and glossy. Spread on top of the cakes when it has set a little.