500g/1lb 2oz frozen red berries, such as raspberries, blackberries and cherries
50驳/1戮辞锄 caster sugar
1 heaped tbsp cornflour
6 tbsp icing sugar
1 tbsp vanilla extract
100g/3陆oz plain chocolate, coarsely grated
600ml/21fl oz double cream
250g/9oz full-fat mascarpone
40ml/1陆fl oz brandy
450ml/16fl oz strong coffee
12 trifle sponges, halved through the middle to make 24