Dry the nori in small pieces in the oven.

In a pan, toast the sesame, kombu, wakame and salt, then deglaze with the soy sauce and mirin.

Let it caramelize, then remove from the pan and let cool.

Mix the cooled toasted mixture with the crumbled nori sheets.

Rinse the sushi rice thoroughly under cold water until the water runs clear, then drain well.

In a saucepan, combine the rinsed rice and water, bring to a boil over high heat.

Reduce to low heat, cover, and simmer for 15 minutes.

Remove the saucepan from the heat and let the sushi rice rest, covered, for 10 minutes.

Meanwhile, in a small saucepan, combine the rice vinegar, sugar and salt.

Heat over low heat until the sugar and salt are completely dissolved, then let cool.

Transfer the cooked rice to a large bowl, pour the vinegar mixture over the hot rice and gently mix with a spatula, taking care not to crush the grains.

Spread the sushi rice in a dish and fan it until it reaches room temperature.

Cover the fish with a mixture of salt and sugar for 10 minutes.

Rinse the fish, then dry it and slice it.

Serve over the rice with spring onion and furikake.