Wheat flour is kneaded together with water, rolled into a rod, rested for a while, then stretched thin by hand and boiled. While it is still warm it is dusted with kinako and with sugar. That is the entire sweet, start to finish.

The name of it comes with a story attached. In the Heian period, a devout wet nurse called Yase took a young nobleman's son to pray at Myorenji temple in Furuno, in what is now Yufu. On the way the boy got hungry and said Yase, uma. Uma is small-child language for something to eat. Each time he said it, she stretched out some dough, boiled it, dusted it with soybean flour, and fed him. Hence, they say, yase-uma.

Whether or not that is what happened, the geography behind the dish is solid. Oita was upland farming country growing grain rather than rice, and a whole culture of flour cooking developed out of that.

Myorenji still makes yaseuma as part of its Obon observances, which means the temple in the story is the temple where the thing is still cooked. It also appears at Tanabata and as an offering. A sweet made of flour, water, and bean powder, and it has stayed attached to the same hillside for a very long time.