125²µ/4Β½΄Η³ϊ evaporated milk
300²µ/10Β½΄Η³ϊ soft light brown sugar
300²µ/10Β½΄Η³ϊ milk chocolate, chopped
vegetable oil, for greasing
75g/3oz dark chocolate (at least 60% cocoa solids), chopped
225g/8oz marshmallows
70²µ/2Β½΄Η³ϊ butter