Cook the rice in the rice cooker. Mix and cool for at least 30 minutes at room temperature.
Meanwhile, in a medium bowl, combine garlic, ginger, miso, water and mirin.
Cut the beef into 2-inch strips. Transfer to the miso mixture. Season with black pepper. Mix well.
In a large pan over high heat, warm ½ tablespoon vegetable oil. Add the beef and cook until cook through. Taste and adjust with salt and sugar. Transfer to a medium bowl.
Prepare a small bowl of water (drinkable). Wet both of your hands with the water. Sprinkle a pinch of salt on one palm. Rub both hands together. Take ½ cup of warm rice and slightly pat down onto one hand. Make a dent in the middle. Add about 1 tablespoon of beef. Carefully cover up the beef with the rice around the edges and roll the whole thing into a ball. Use both of your palms to gently pressure the rice ball into a triangle shape. Repeat with the rest of the rice.
When ready to serve, wrap each rice ball with a piece of seaweed and sprinkle with furikake. Serve immediately or at room temperature.
I used white miso, because I have leftover at home. You can also use red miso or a mixture of both. But red miso tends to be saltier, you may have to use less when cooking.
Thinly sliced beef can be bought in Asian supermarkets, like Mitsuwa, 99 Ranch and H-mart.
If you can’t find thinly sliced beef, you can use ground beef as well.
The beef should taste saltier and stronger than normal, because they are used as filling.
Do not wrap onigiri with nori (seaweed) until ready to serve. Seaweed gets soggy real quick.
Furikake is a dried seasoning for rice. It adds extra flavors to the onigiri. They come in many flavors, like salmon, seaweed, shrimp, bonito. The classic is the seaweed, which is what I used in this recipe. It is best with the miso beef. You can find Furikake in most Asian supermarkets or from Amazon.