Ingredients
4 cups of freshly cooked Japanese-style rice (Each onigiri requires about a cup of cooked rice.)
2 sheets of nori seaweed, cut into 3cm/2 inch wide strips
Salt (just a pinch here and there)
Fillings. Some classic fillings are pickled plum (umeboshi), flaked cooked salted salmon (shake or shiozake), cooked salty cod roe (tarako), chopped up pickles (tsukemono), but you can fill it with anything you like or have a taste for.
Preparation
The key to making good onigiri is to have freshly cooked, hot rice. You can’t make good onigiri with cold rice.
Wet your impeccably clean hands with cold water, and sprinkle them with salt. Take 1/4th of the rice and place on one hand. Make a dent in the middle of the rice with your other hand. Put in about 1 tsp or so worth of filling in the dent.
Working rapidly, wrap the rice around the filling, and form into a ball. To make the traditional triangular shape, cup your hand sharply to form each corner, and keep turning it until you are happy with the shape. Practive makes perfect.
Wrap the rice ball with 1-2 strips of nori seaweed.
Repeat for the rest of the rice.