The entire prefecture centering on Nagoya city

Sweet potatoes, flour

“Oni-manju” was made with sweet potatoes and wheat flour, which were relatively easy to obtain during and after the war when food was scarce, and it became popular as a staple food instead of rice. It is said that the name was given because the way the cubed sweet potatoes look like the horns or a metal stick of an oni (ogre). It has various names such as "Imo-uiro", "Imoman", and "Imo-manju" depending on the region. During the war, the quantity of sweet potatoes was more important than their taste, so a variety called "Gokoku-imo" was produced, which had a large yield. However, unlike the sweet potatoes of today such as Beni-azuma, Beni-haruka and Annou-imo, which have a sweet taste and a smooth texture, Gokoku-imo was watery and did not have umami, so it is said that the "Oni-manju" was born from the ingenuity of finding ways to make it more delicious. Later, during the period of rapid economic growth, it became popular as a filling and inexpensive snack for farmers.

Although it is most often made in the fall, when sweet potatoes are harvested, "onimanju" is always available at Japanese confectionery shops, and is therefore eaten throughout the year.

Sweet potatoes cut into 1 cm cubes are placed in a dough made of flour and sugar, and steamed before eating. The red color and texture of the sweet potato skin can be enjoyed by leaving the skin on. It can be eaten warm or cold, but if you reheat it in the microwave for 20 to 30 seconds with plastic wrap, you can enjoy the freshly made texture.
Onimanju" is characterized by its firm and heavy texture, which makes it very filling. In recent years, however, some people enjoy eating it with a fluffy, steamed bread-like texture, or with apple cubes in place of sweet potatoes.
Many of the sweet potatoes sold at Japanese confectionery shops have been "honey-simmered" in advance. At home, sweet potatoes are simply sprinkled with salt and sugar.

Some communities are making efforts to pass on the tradition by incorporating it into school lunch menus and offering cooking classes in conjunction with learning about sweet potato cultivation. In addition, because it is easy to prepare, it is also made at home and passed down from generation to generation.