Wasabi is a spice traditionally prepared from a plant from the cabbage family. Its root is used as a spice and has a very strong flavor. The root is smashed up into paste and used as a condiment. Its hotness is more like hot mustard or horseradish than chili pepper, because it irritates the nose more than the tongue. Eating too much wasabi can cause a very painful feeling in the nose. The plant grows naturally in Japan. It is often eaten with sushi.
Wasabi needs clean water and a cool climate. It is difficult to grow wasabi. There are two ways to grow wasabi. One way is to grow wasabi in water. The other way is to grow wasabi in field.
Because the wasabi plant is so hard to grow, real wasabi is very rare and expensive. Most wasabi is a green paste that is really made from horseradish, mustard and food coloring. Real wasabi is white, not green.