70g/2陆oz packet dried sour cherries
100驳/3陆辞锄 plain flour
175g/6oz soft light brown sugar
175g/6oz caster sugar
50驳/1戮辞锄 cocoa powder
125驳/4陆辞锄 plain dark chocolate
125驳/4陆辞锄 white chocolate
200g/7oz butter, plus extra for greasing
4 large free-range eggs