1. Preparation
Rinse 1 cup of uncooked sushi rice under cold water until the water runs clear.
Soak the rinsed rice in water for 30 minutes to 1 hour to ensure proper cooking.
While the rice is soaking, wash and roughly chop 5-6 shiso leaves.
Prepare a small bowl with salt for seasoning the rice.
2. Cooking Rice
After soaking, drain the sushi rice and place it in a rice cooker or a pot.
Add 1 ⅓ cups of water to the rice cooker or pot.
If using a rice cooker, close the lid and set it to the sushi rice setting. If using a pot, bring the water to a boil, then reduce heat to low, cover, and simmer for 18-20 minutes.
Once cooked, remove the rice from heat and let it sit covered for an additional 10 minutes.
Fluff the rice with a wooden spoon or spatula and add a pinch of salt and the chopped shiso leaves. Mix gently to combine.
3. Shaping Onigiri
With wet hands to prevent sticking, take a handful of the rice mixture.
Form the rice into a triangle or oval shape by pressing it gently but firmly.
Make sure the onigiri is compact and holds its shape.
Repeat this process until all the rice mixture is shaped into onigiri.
4. Serving
Wrap each onigiri with a shiso leaf or a strip of nori (seaweed) if desired.
Serve the shiso onigiri at room temperature or chilled, making them perfect for a bento box or a snack.