Wash the rice under cold running water until the water runs clear;
drain thoroughly. Place the rice in a pan with the water and bring to the boil. Reduce the heat and simmer for 4 to 5 minutes or until all the water
has been absorbed. Reduce the heat to very low, cover and cook for another 4 to 5
minutes. Remove the pan from the heat and leave, covered, for about 10
minutes. Add the combined vinegar, sugar and salt to the rice, tossing with a
wooden spoon until the rice is cool.
Cut the fish into thin strips. Cut the cucumber and avocado into matchsticks about 5 cm in length. Place a sheet of nori on a piece of greaseproof paper or on a sushi
mat on a flat surface, with the longest sides at the top and bottom; pat
a quarter of the rice over about half of the nori sheet along one long
side, leaving a 2 cm space around the sides. Spread a very small amount of wasabi down the centre of the rice. Arrange a quarter of the pieces of fish, cucumber, avocado, if
using, and ginger along the top of the wasabi stripe. Using the paper or mat as a guide, roll the nori up firmly from the
bottom, enclosing the rice around the centered ingredients.
Press the nori edges together to seal the roll. Using a sharp flat-bladed or electric knife, cut the roll into 2.5
cm rounds. Repeat with the remaining ingredients. Serve the Sushi on individual small plates with small bowls of
sauce and extra wasabi to be mixed to taste to make a dipping sauce.
Note : Make sure the fish for Sushi is extremely fresh. Sushi can be
made up to 4 hours in advance and kept, covered, in the refrigerator.
Slice the rolls just before serving. Sushi mats, available from Asian food
stores, makes the rolling of the Sushi much easier.