Uirō is a sweet Japanese cake consisting of sugar, rice flour, and water. The cake is traditionally steamed until it develops a chewy texture. It dates back to the 16th century, when it was used as a part of Japanese tea ceremonies, a tradition that is also practiced today.

There are a number of variations on the cake, so it can be flavored with ingredients such as matcha, chestnuts, strawberries, or azuki bean paste. Although it's made from the same ingredients as mochi, the method of preparation is different - uirō is poured into a mold and steamed, while mochi is pounded in order to become sticky.