300g/10陆oz frozen blackberries
200g/7oz plain flour
2 tsp baking powder
200g/7oz caster sugar
50驳/1戮辞锄 caster sugar
50驳/1戮辞锄 cocoa powder, sifted
1 tbsp icing sugar
录 tsp fine sea salt
1 tsp vanilla extract
100g/3陆oz dark cooking chocolate, broken into squares
200ml/7fl oz double cream
150ml/5fl oz double cream
2 medium free-range eggs
125ml/4fl oz full-fat milk