wheat. It is popular especially in western Japan. It is usually served chilled in the summer and hot in the winter. Today it is so wet that I 'd like to eat something cold and flavor with spices. I put several condiments typical for Japanese cuisine; Myouga, Tade, Shiso and Kaiwaredaikon on noodles. I will describe them on the next entry.
There are many kinds of topping and each has proper name. For example, udon topped with Aburaage is called Kitsune-udon. Kitsune means a fox and the name is derived from the Japanese folktale in which a fox likes Aburaage, deep-fried tofu. Udon topped with raw egg is called Tsukiki-udon. Tsukimi means a moon-viewing and the name coms from comparing a raw egg yolk to moon.
Forgetting to say, I sometimes prepare Salad udon for bento. I put sauce for udon on it just before eating.