Gently mix together the rice and yukari shiso salt in a bowl. Form into onigiri .
Preheat a grill to medium. Grill the onigiri for about 8 minutes, turning twice. Grill the edges of the onigiri triangle, too, about 20 seconds per edge. The onigiri will have a crispy, caramelized crust when they're done. Serve immediately.
