Spicy Tuna Roll

Rinse 360g short-grain sushi rice under cold running water for 2 minutes until runoff water is almost clear, then drain fully for 10 minutes. Combine drained rice with 480ml (2 cups) cold water in a rice cooker, run the standard white rice cycle (≈20 minutes cook time), then let rice rest covered for 10 minutes after the cycle ends. While rice is still warm (≈43C/110F), gently fold in 60ml rice vinegar, 25g granulated sugar, and 5g fine sea salt until evenly distributed. Spread seasoned rice in a thin layer on a rimmed baking sheet to cool to room temperature (21C/70F); do not refrigerate, as cold temperatures make rice hard and grainy.

In a medium glass mixing bowl, combine 225g finely diced sushi-grade ahi tuna, 45g Kewpie mayonnaise, 30g sriracha hot sauce, and 5ml toasted sesame oil. Gently fold with a silicone spatula to coat tuna evenly in the creamy, pale orange sauce, keeping 1/4-inch tuna chunks intact (do not over-mash into a paste). Adjust sriracha to reach a medium heat level that does not mask the tuna’s mild, briny flavor, then chill the mixture in the refrigerator for 10 minutes before assembly.

Lay a bamboo sushi rolling mat (makisu) on a clean, dry countertop, and wrap it tightly in plastic wrap to prevent rice from sticking. Place 1 full nori sheet shiny-side down on the center of the mat. Fill a small bowl with 120ml (1/2 cup) cold water mixed with 5ml (1 tsp) rice vinegar to dampen fingers during assembly. Arrange cucumber matchsticks, avocado strips, chilled spicy tuna, and toasted sesame seeds within arm’s reach for efficient rolling.

Dip your fingers in the vinegared water to prevent sticking, then scoop 1/4 of the cooled rice (≈150g) onto the nori sheet. Spread rice into an even 5mm (1/4-inch) thick layer across the nori, leaving a 2cm (3/4-inch) bare nori strip at the top edge for sealing. Sprinkle 1/4 of the toasted sesame seeds over the rice, then flip the nori so the rice side faces down against the mat. Lay 1/4 of the cucumber, 1/4 of the avocado, and 1/4 of the spicy tuna in a tight, straight horizontal line across the nori, 2cm from the bottom edge.

Lift the bottom edge of the bamboo mat up and over the filling line, tucking the mat edge firmly against the filling to create a tight, sealed core. Squeeze the mat around the roll with even, gentle pressure (avoid squeezing so hard that filling oozes out) to form a uniform 4cm (1.5-inch) diameter cylinder. Continue rolling upward until you reach the bare nori strip, then dab a tiny amount of vinegared water along the strip to seal the roll closed. Repeat layering and rolling for the remaining 3 nori sheets and fillings to make 4 total rolls.

Let assembled rolls rest for 2 minutes at room temperature to set, then use a very sharp, wet chef’s knife to cut each roll into 8 even 2.5cm (1-inch) thick pieces. Wipe the knife blade clean with a damp cloth between every 2 cuts to prevent sticking and ragged edges. Arrange cut pieces seed-side up on a dark ceramic serving platter, paired with small ramekins of soy sauce, pickled ginger, and wasabi paste for serving.