Okay, basically flummery is cold porridge that's been allowed to go off (in the US I understand you say allowed to spoil); but only in a good way.
Or so they say.
For a classic flummery you need:
500g fine oatmeal, 1 litre water, 1 litre buttermilk, salt to taste.
Heat the water and buttermilk to body temperature, then pour it over the oatmeal, cover, and leave in a warm spot to ferment.
After three days (when the liquid will be sour) strain the mixture through muslin and discard the oats. Transfer the liquid to a large pan and bring to a boil. Continue cooking, stirring all the while, until the mixture thickens almost to the point of being solid and then season with salt.
Ladle into bowls, allow to cool until completely cold, pour over hot milk, and then - this is the problematic bit for me - I'm afraid you have to eat it.
Still, never mind, there are other sorts of flummery. Flummery can be nonsense that's used to something to make something seem more important or interesting than it actually is.
Lastly, and most lovably, flummery can also mean harmless flattery. And even those who don't fancy a bowl of cold rancid porridge are bound to enjoy a little of that.
Word To Use Today: flummery. This word comes, like the recipe, from Wales. It's an English approximation of llymru.