That is, a cake for Twelfth Night (which, this year, fell on Sunday, 5th January), The ‘first day of Christmas’ being Christmas Day. The ornaments referred to were very elaborate and presumably in this particular year an element of them contained something not very nice at all.
This could well have been arsenic poinsoning, because the green dyes used in those days contained that element. Or perhaps white arsenic (a white powder which was often used to control rodents) was used instead of flour
It seem the appearance was more important than the taste of the cake!
“Twelfth Cakes. – The ornaments which are generally used for twelfth-cakes have been nearly attended with fatal consequence in this town: several persons are suffering from partaking of this highly deleterious compound. Surely the parties preparing them should have some thought for the health of others. Of several persons poisoned, all are believed to be now out of danger, although some are suffering extremely from the effects.”
The Stamford Mercury, 6th February, 1846.
Mary Berry’s recipe for the cake can be found here. And it definitely does not contain anything nasty!