So I know of two ways, one way is what happens with commercial Cantonese cooking:
- Add rice and water to your rice cooker, and throw in a knob of butter, diced, mix it all amongst the rice so it will be vaguely even;
- Cook rice as per normal.
Reasons: adding fats help to keep rice from sticking. They do this so they can make fried rice with fresh rice, rather than waiting for rice to stale for 1+ days in the fridge.
The other way is from Persian cooking:
- Add rice and water to a pot and par-boil;
- Once par-boiled, remove and steam the rest of the way.
- Sometimes they will add some oil too.
Reasons: possibly adding fats too, but also, not oversaturating the rice with water will mean they are harder, and can retain their shape better.
Just a bit of a different take to @Chee’s Burgers’ answer.