Onigiri (Japanese Rice Balls)

Method

1. 1Rinse the rice in cold water, swirling with your hand and draining, until the water runs clear — usually four or five changes. This removes surface starch that would otherwise turn the rice gummy.
2. 2Cook the rice with 440 ml water, using slightly less water than usual so the grains stay firm enough to press. Once cooked, leave it covered off the heat 10 minutes, then fold it gently with a paddle to release steam.
3. 3Spread the rice in a wide bowl and let it cool to around body temperature, 15 minutes or so. It must be warm but not hot: hot rice falls apart and burns your hands, fully cooled rice will not bind.
4. 4Prepare the fillings. Salted salmon is sold raw, so cook it first: grill it or cook it in a dry frying pan over medium heat, turning once, until the flesh is opaque all the way through and flakes easily. Let it cool a little, then flake it, discarding skin and bones. Drain the tuna and mix it with the mayonnaise and soy sauce. Pit the umeboshi. Cut the nori sheets into wide strips.
5. 5Set out a bowl of water and a dish of sea salt. Wet both palms, then rub a good pinch of salt between them — this seasons the outside of the rice and stops it sticking.
6. 6Take about 100 g of rice into one palm, press a hollow in the centre with a finger, add a teaspoon of filling, and close the rice over it. Cup your hands into a V, press firmly, rotate the ball 120 degrees, and repeat three or four times until a triangle forms. Don't overwork it or the rice compacts into a dense lump.
7. 7Wrap each onigiri in a strip of nori. For crisp nori, wrap at the moment of eating; for soft nori that clings to the rice, wrap while still warm. Scatter with sesame seeds and serve at room temperature.