Walliser Cholera

There is a persistent rumour that the dish is indeed named for the disease Cholera, after a particularly bad outbreak in the 1830. People in the Wallis stayed home to avoid contamination and were forced to use things they already had in their larder and gardens to feed their families.

More likely, however, is that it's named after the glowing coal in the fireplace where the pan would have sat to bake.