The first step is to cook the rice in a rice cooker for approximately 20-25 minutes or according to package instructions.
In a small bowl, mix the soy sauce, miso paste, and dilute it with 1 tsp of water.
Once the rice is cooked, wet your hands, so the rice doesn’t stick, and scoop a handful of rice into your hand. Shape the rice into a big round or oval ball. You can make any shape you prefer, including triangles, but a ball is the easiest to make, especially for beginners.
Once shaped, squeeze the rice ball firmly to help the rice stick and maintain its shape. You must make three rice balls.
Heat the oil in a cast-iron pan. Add half of the butter and wait until it starts to melt. Now place the three rice balls.
Brush the soy and miso sauce on each rice ball. Grill the onigiri for about 7 minutes on one side until they are well browned and cooked.
Now flip over, brush each with soy and miso sauce and add a small piece of butter on top of each. Continue to cook for another 5 minutes or until crisp and golden brown. The butter will help the rice develop a nice crispy crust.
Once ready, plate and garnish with a sprinkle of sesame seeds.