225g/8oz plain flour
1陆 tsp bicarbonate of soda
100驳/3陆辞锄 soft light brown sugar
125g/4陆oz golden caster sugar
40驳/1陆辞锄 cocoa powder
50驳/1戮辞锄 sunflower oil
1 tsp vanilla extract
100驳/3陆辞锄 dark chocolate, 55-65% cocoa solids
100驳/3陆辞锄 chocolate chips (dark, milk or white chocolate)
50驳/1戮辞锄 unsalted butter
200ml/7fl oz buttermilk
2 free-range eggs