Strained azuki paste is mixed with wheat flour and worked together thoroughly. The mixture is laid on a bamboo sheath dampened with water, folded up, tied with bamboo cord, and steamed for about fifteen minutes once the water is boiling. It comes out hot and is pressed flat under a light weight.

The wheat flour is the interesting part. A proper neri-yokan needs agar, and agar was hard to get in Omi, which has no coast of its own. Wheat flour went in as the binder instead, and the texture that resulted is chewier and less glassy than a yokan usually is.

The name has attracted at least three explanations, and the sources do not choose between them.

One says that apprentices, dettchi, sent out to serve in Osaka or further, could afford this on the wages they had when they came home. One says the opposite direction: that they made it at home and carried it back as a gift for the master and the head clerk. One says it has nothing to do with apprentices at all, and comes from a confectioner's word, dettchiru, meaning to knead things together. It was selected as one of Shiga's food cultural properties in 1998. A sweet made out of what was missing kept the name, whichever of the three names is the right one.