Place the rice, salt and 4 cups water in a pot and bring to the boil over medium heat. Reduce the heat to low and simmer, covered, for 20 to 25 minutes, until the rice is cooked and all the water has evaporated. Let sit for 5 minutes.
Stir the vinegar into the rice, then tip into a large round dish. Press the rice with moistened hands to prevent sticking.
Serve warm or at room temperature. Just before serving, sprinkle the rice with the black sesame seeds and garnish with microherbs.