Place rice in a sieve and wash until water runs clear (at least six or seven times).
Set aside for 30 to 60 minutes (it must be left until dry).
Bring rice and water to the boil. Reduce heat and simmer for 20 minutes. Remove from heat and allow to rest for 15 minutes.
Mix vinegar, sugar and salt together.
Place rice in a wooden or ceramic (not metal) bowl and add vinegar mixture. Mix lightly.
Spread rice onto a couple of baking trays and then, using a large spoon and a piece of card, simultaneously stir and fan the rice to cool it. This is important, so as to cool the rice as quickly as possible. (The fridge will not do. This is to prevent the rice from getting too starchy and to achieve a good shine.)
When the rice is cool, start preparing the sushi.
Spread wasabi paste on a slice of fish.
Place fish, wasabi-side-up, in your left palm. Top with a small ball of rice.
Curl your palm and fingers to press the rice onto the fish.
Turn and shape with palm closed.
NOTE: Lightly wet your hands before shaping the rice into balls (this is a messy job and is best done with a few friends and a fair amount of wine).
SUGGESTED TOPPINGS: Avocado, cucumber, spring onion, very fresh fish (salmon and tuna are great), smoked eel, nori (seaweed), steamed prawns and salmon roe.
SERVE with: Pickled ginger, wasabi and soya sauce.
IMPORTANT NOTE: Remember that hygiene is essential when working with raw fish. Slice it against the grain using a very sharp knife.