Fermented milk: buttermilk is poured into a pan and left to stand until it begins to ferment, at which stage about 1/4 or 1/3 part of fresh milk is added. It is allowed to ferment again, after which a watery fluid settles beneath it and is drawn off through a tap. Each time some is removed and eaten, fresh milk is added again and the whole process is repeated for as many as 15 days, by which time this has become thick and delicious.