01 -
Rinse the sushi rice thoroughly in a fine mesh strainer under cool water until the water runs clear. Cook the rice according to package or rice cooker instructions.
02 -
Combine rice vinegar, sugar, and Kosher salt in a small saucepan. Bring to a simmer over medium-high heat and whisk until fully dissolved. Set aside.
03 -
While the rice is still warm, gently fold the sushi vinegar into the rice using a rice paddle or spatula, being cautious not to mash the grains.
04 -
Line a small rectangular tray or Tupperware with plastic wrap. Evenly press the seasoned rice into a flat, compact layer about 1.5 cm thick. Cover tightly with plastic wrap and refrigerate for several hours or overnight.
05 -
Dice the sushi-grade tuna into small cubes, then further chop until the texture is finely minced. Place into a large mixing bowl with sliced scallions.
06 -
In a bowl, whisk together Kewpie mayonnaise, Sriracha, and ponzu sauce until smooth. Pour over the chopped tuna mixture and mix thoroughly to combine. Cover and refrigerate until ready to use.
07 -
With slightly damp hands, cut the chilled rice into rectangles approximately 5 cm x 2 cm. Heat neutral oil in a large skillet over medium heat, then fry the rice pieces in batches for about 2 minutes per side, or until golden and crisp. Transfer to a rack lined with paper towels to drain.
08 -
Place a generous tablespoon of spicy tuna mixture atop each crispy rice piece. Garnish with black sesame seeds and a thin slice of jalapeño. Drizzle with extra spicy mayo if desired, then serve immediately.