My fail-safe recipe using a pot over gas. (Rice cookers are rare in
Africa)

I don't find the type of rice to be as important as the cooking
method. Certainly, the shorter grains help a nigiri to stay together,
and if there's short-grain "sushi" rice in the cupboard, I'll use it.
Otherwise, plain ol' Tastic or Rio (cheap, long-grain, off the shelf
stuff available here in South Africa) does just fine.

Place 500ml (2C) uncooked rice in a sieve or colander and rinse,
agitating under running water for at least five minutes, until NO more
white starch runs down the drain.

Allow to stand and drain for at least fifteen minutes, although an
hour is recommended.

Place washed rice on stove with equal volumes of cold water (500ml
water to 500ml rice). A heavy based stainless steel pot with a lid
that seals well is essential - flimsy aluminium pots will let out the
precious steam and burn on the bottom.

DON'T MESS WITH IT! Stirring will release more of the loose starch
you've just taken all that time to remove.

As soon as the water begins to boil, cover with a tight-fitting lid
and turn the heat down as low as possible, just enough to maintain a
gentle boil, for 15 min.

Remove from heat and allow to stand covered for a further 15 min. DO
NOT OPEN THE LID!

In the meantime, prepare your enzymes. For 500ml rice, I use:

75ml (5T) rice vinegar
10ml (2t) sugar
2.5ml (0.5t) salt

For a slightly zestier flavour, I enjoy replacing one tablespoon
(15ml) of the rice vinegar with pure lime juice.

Heating this slightly in a microwave helps disolve the sugar.

When the rice has stood covered for its 15 minutes off the heat,
transfer it to a non-metalic bowl. Plastic or bamboo is best. Glass
can be a bit sticky and any metal will affect the flavour due to
reaction with the vinegar.

Pour over the liquid and toss using a wooden spoon or large
chopsticks. You want to get some air into the mixture to bring it down
to room temperature - otherwise it'll just continue cooking in its own
heat and get stodgy.

This recipe has succeeded repeatedly for both sushi preparation (keep
your hands wet) and as a sticky rice with Thai curries.

Gavin