Chocolate banana cupcakes

These are based on Julie Goodwin's Lemon Diva Cupcakes, but with cocoa powder and banana instead of lemon zest.

CUPCAKES
100 g butter
165 g sugar (I use Tate&Lyle caster sugar)
A splash vanilla extract (e.g. Nielsen-Massey)
2 eggs
200 g flour
1,5 tsp baking powder
3-4 tbsp cocoa powder
100 ml milk
2 very ripe bananas, mashed

Beat butter, sugar and vanilla extract. Add the eggs one by one and mix well. Mix flour, baking powder and cocoa, then stir in about half into the egg and butter mixture. Add half the milk, then the rest of the flour mix and the rest of the milk. Lastly stir in the mashed bananas. Divide mixture into lined muffin pan. I got 10 cupcakes out of this recipe. Bake at 180C for 18-20 mins.

ICING
60-70 g chocolate, 70% cocoa solids
25 g butter
2-3 tbsp icing sugar
50-100 ml single cream

Melt chocolate, butter and icing sugar together over low heat, then add cream until the mixture emulsifies. Leave to cool.