225g/8oz fresh raspberries and blueberries
1 level tsp baking powder
100驳/3陆辞锄 caster sugar
25g/1oz cocoa powder, plus extra for dusting
icing sugar, for dusting
100驳/3陆辞锄 self-raising flour
300g/11oz dark chocolate (no more than 40-50 per cent cocoa solids), broken into squares
double cream
2 large free-range eggs
100驳/3陆辞锄 margarine, plus extra for greasing
450ml/16fl oz whipping cream
2 tbsp brandy