1. In a large bowl, put rice, and rinse it with cold water.
2. Mix, and rinse it again. Repeat until the water becomes clear.
3. Put rice in rice cooker bowl.
4. Pour water into it.
5. Select sushi pre-washed option from the menu. Cook for 45-60 minutes.
6. In a bowl, add salt, rice vinegar, and brown sugar. Mix until sugar dissolves.
7. Transfer steaming rice into a large bowl. Place it under the fan, and pour vinegar mixture in it. Gently mix to combine as shown in the video, keeping in mind that the rice is not smashed.
8. Prepare rice base, roll it with tuna, cut into slices, and serve with spicy sauce.