These are a great, tasty and easy staple for the carb component of your bento box. This is how I make them, I'm sure there are many other ways, but this is how I like them.
First rinse 1 Cup of short grain rice three to four times and drain (not until dry, leave some moisture.
NOTE: Australian Cup measurements are 250mls = 1 Cup
Add 1 1/4 Cup of water and cook in a rice cooker. Or alternatively on a low heat in a saucepan with a tight fitting lid until 'tunnels form' I find that's at usually about 12-15 mins.
1 Tbsp rice wine vinegar NOTE: 1 Tbsp is 20mls
1/2 Tbsp water
1/2 Tbsp sugar
Mix through the cooked rice while fluffing it with a rice paddle. If you can stand near an open where there is a breeze it's good, it'll cool the rice quickly and give it a nice sheen.
Place an amount in a rice molder and put the top down to press the rice into shape. Don't overfill the container or you will have rock like Onigiri.
You can also do this manually with your hands, I find the round disc shape is easier than a triangle if you are hand shaping the Onigiri.
Take the top off the mold then invert and press out onigiri.
Wrap in cling wrap individually (this stops them from drying out), and put in fridge.
When they are cool, wrap in nori pieces and decorate with face :D and serve!
This recipe will make about 7 Onigiri at about 195 calories each.