Wash the rice until the water runs clear. This takes longer than you think. Soak the rice for 30 minutes and then drain. Transfer to a rice cooker along with 1.5 cups water and cook.
While the rice is soaking and cooking, prepare your filling of choice.
For the Spicy Kimchi Tuna, heat a drizzle of sesame seed oil on medium heat. Once it’s warm, add the green onions, kimchi and a little bit of kimchi juice. Sauté for 3 minutes. Add the tuna and guchujang and mix until fully incorporated. Put into a bowl and set aside.
For the Salmon Furikake, mix all the ingredients together in a bowl and set aside.
Once the rice is done cooking, add a little bit of rice vinegar and sea salt and mix. Let the rice cool enough to be able to handle.
Wet your hands (I like to keep a bowl of water near by so I can constantly wet my hands) and scoop 1/4th cup rice into the palm of your hand. Make an indentation and place your filling of choice in the middle. Shape the rice around the filling into a triangle, ball, or cylinder shape.
Place a sheet of seaweed on the bottom. Usually you're supposed to use unflavored seaweed sheets that you cut into the desired sizes but I like to use seasoned seaweed. (1) Because I like the extra kick of flavor and (2) because you can buy seasoned seaweed in pre-cut packets.
Sprinkle the rice ball with your choice of rice seasoning (furikake). My personal favorites are nori komi furikake and salmon furikake. Serve with roasted seaweed sheets and pickled plums (umeboshi).