If a small container of stinky yeast mixture should arrive at your door with a note, make sure you look after him: his name is Herman, and he's the latest food fad sweeping the UK.
And not for the first time, either; many will remember Herman cakes from the 70s when they first became popular. The culinary equivalent of a chain letter, the mixture is nurtured for nine days, during which it expands, before being divided into four sections. On the 10th day you pass on three of the parts to friends and make a cake for yourself with the fourth. In theory, one starter mix could be passed around for ever.
Each Herman comes with precise instructions that will tell you when he is hungry, when he is thirsty, and when he should be stirred. Over the 10 days, the mixture (which must only be covered with a tea towel and never put in the fridge) will bubble away, emitting a pungent smell not dissimilar to a brewery. When you come to make your Herman into a cake, you are instructed to add ingredients including apples, cinnamon and raisins, although others will also throw in anything from chocolate chunks to glaced cherries or walnuts. The end result is a bit like panettone.
The idea of Herman cakes is believed to have originated with the Amish, who use a similar yeast mix to make sourdough bread, which is then passed around the community. While its current popularity has spread through websites such as Mumsnet, where it has many a fan, it's found an altogether younger demographic, too. Lizzie Boon, a student nurse, was given her starter mixture by her mother.
"She was given some from my dad's colleague's wife,'' Boon says.
