Takuan is a popular Japanese pickle made from daikon radish. The ingredients for making takuan include daikon radish, salt, and rice bran. To make takuan, start by peeling the daikon radish and cutting it into thick slices or sticks. Then, sprinkle the daikon with salt and let it sit for a few hours to draw out the moisture. After that, rinse the daikon and place it in a container. Cover the daikon with rice bran and let it ferment for several days to several weeks, depending on the desired level of sourness. Takuan has a crunchy texture and a slightly sweet and tangy flavor. It is often served as a side dish or used as a topping in sushi rolls.