Japanese senbei is a traditional type of cracker that has been enjoyed as a snack in Japan for centuries. They are made from rice flour, mixed with natural ingredients such as soy sauce, salt, sugar, and mirin (a sweet cooking sake) to create a dough. The dough is then rolled out into thin sheets and cut into circles or squares, which are then baked or grilled until they are crispy and golden brown. There are various types of senbei, from thin and crisp to thick and crunchy. 
Popular senbei flavors are soy sauce, seaweed, sesame seeds, or wasabi. They can also be coated with a sweet or savory glaze, or have a filling such as peanuts or red bean paste.
Senbei crackers are often enjoyed as a snack with tea or sake, and are a popular souvenir for tourists visiting Japan. They can even be used in Japanese cuisine as a garnish for soups and salads, or crushed and used as a crunchy topping for rice dishes.