Rinse the uncooked Japanese short-grain rice until water runs almost clear. Place rice in a rice cooker with water and a piece of kombu. Let it soak for 20–30 minutes, then cook. Discard kombu after cooking.

Transfer the rice to a wooden sushi oke or a lined baking sheet. Pour seasoned rice vinegar over the rice while it’s hot. Using a rice paddle, gently slice the rice at a 45-degree angle to incorporate the vinegar without breaking the grains. Fan the rice vigorously while slicing to cool and remove excess moisture. Cover with a damp towel to keep it moist.

Thinly slice the red onion, place it in a jar or bowl, cover with seasoned rice vinegar, and set aside to pickle.

Whisk together the Kewpie mayonnaise, sriracha sauce, and a splash of lime juice. Set aside.

Halve the cucumbers lengthwise, scoop out the seeds, and slice them into long strips. Julienne the carrot. Cut the fried tofu cutlet into slabs, then into long sticks.

Halve and pit the avocados carefully. Cut into quarters and remove the skin. Slice lengthwise and brush with lime juice to prevent browning.

Place one nori sheet shiny side down on a bamboo rolling mat. Spread 1 cup (150 g) sushi rice evenly, leaving a ½ inch strip at the top edge uncovered.

Spread a thin line of spicy mayo about 1½ inches from the bottom edge. Layer cucumber strips, avocado slices, tofu sticks, pickled red onion, and carrot strips evenly across the rice.

Carefully lift the bottom edge of the mat, folding the nori over the fillings tightly. Continue rolling firmly until the roll is sealed. Squeeze the bamboo mat to shape the sushi tightly. Wrap finished roll with plastic wrap to prevent drying.

Using a very sharp knife, cut the sushi roll in half, wiping the knife clean with a wet cloth between cuts. Then slice halves into quarters, and quarters into halves to yield 8 pieces per roll.

Arrange on a platter and serve with soy sauce, wasabi, and pickled ginger.