300g/10½oz frozen blackberries
200g/7oz plain flour
2 tsp baking powder
200g/7oz caster sugar
50²µ/1¾´Ç³ú caster sugar
50²µ/1¾´Ç³ú cocoa powder, sifted
1 tbsp icing sugar
¼ tsp fine sea salt
1 tsp vanilla extract
100g/3½oz 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