Wasabi is an important part of Japanese cuisine, especially sushi. The use of wasabi has been recorded in Japan in 14,000 BC. It is similar to horseradish in flavour and is actually a stem and not a root. Wasabi takes two years to grow enough to be harvested and is therefore quite expensive. Pastes available in supermarkets, which contain more horseradish and food colouring, cannot compete with fresh wasabi. The pungency of wasabi, which is caused by the vapour the plant produces, is comparable to that of mustard. It works well when used to cut through oil in food and so goes well with fried prawns. Crispy, fried prawns served with a wasabi and mayonnaise dressing make a tasty appetiser. This recipe is uncomplicated and can be prepared using only a few ingredients.