175g/6oz plain flour
录 tsp baking powder
1 tsp bicarbonate of soda
275g/9戮oz soft dark brown sugar
50驳/1戮辞锄 muscovado sugar
50驳/1戮辞锄 cocoa powder
220g/8oz icing sugar
pinch salt
220g/8oz good-quality dark chocolate (minimum 70% cocoa solids)
110g/4oz butter, softened
100g/3陆oz soft butter
250ml/9fl oz double cream
2 large free-range eggs
200ml/7fl oz dark ale, plus 4 tbsp for the icing