The barm cake is a soft flat roll that comes from North West England. It is traditionally leavened with barm, which is a sourdough yeast. The main ingredient in barm cake is sourdough flour. It is very simple to make and is a popular dessert in the North West.
The barm in the name is from the foam that rises on top of the beer. The traditional barm cake is quite bland, but it is actually made with commercial yeast. The name is derived from the fact that the bread is used as this leaven. The ingredients in barm cake are very simple, and the process is relatively simple.