125g/4陆oz crunchy peanut butter
150驳/5陆辞锄 plain flour, sifted
225g/8oz caster sugar
175g/6oz icing sugar
100驳/3陆辞锄 macadamia nuts, chopped
1 vanilla pod, split, seeds scraped out with a knife (the pod can be reserved for another recipe)
225g/8oz white chocolate, chopped
225g/8oz butter, melted, plus extra for greasing
75驳/2戮辞锄 butter
4 free-range eggs
50-75ml/2-4fl oz milk (optional)