Rice | Scoop one cup of medium-grain rice into the pot of a rice cooker. Rinse with sink water until the water runs clear of starches. Discard the starchy water. Add enough filtered water until the rice is submerged and with 1/2 inch of water from the surface. Steam. Once the rice is warmed, add rice vinegar, sea salt, and sugar. Mix. Deposit into a container and flatten until 2 inches thick. Cover the surface directly with Saran Wrap to prevent drying out and seal with a lid. Refrigerate overnight.

Spicy Tuna | Add kewpie, sriacha, soy sauce, and sesame oil into a bowl. Mix until homogenous. Add tuna and scallions. Mix until evenly coated.

Crispy Rice | Carefully remove the chilled rice from the fridge, square the edges, and divide in half. Set a skillet over medium high heat. Add oil and let it come to full temperature. Add 1 slab of crispy rice and sear until golden brown. Flip to sear the other side and repeat with remaining crispy rice.