1 lemon, zest only
6 tbsp golden syrup
1 tsp baking powder
175g/6oz soft dark brown sugar
75²µ/2Β½΄Η³ϊ caster sugar
175g/6oz self raising flour
1 vanilla pod, split in half lengthways and seeds scraped out
175g/6oz butter, softened
200ml/7fl oz double cream
4 medium free-range eggs
6 free-range egg yolks
200ml/7fl oz milk