Rinse the sushi rice in cold water until the runoff is clear, then cook with 250 ml of water according to package directions. In a small bowl, whisk the rice vinegar, sugar, and salt together; fold into the warm cooked rice gently, then allow to cool to room temperature.

Preheat your oven to 200 °C (180 °C fan / 204 °C). In a medium bowl, whisk together the white miso, tamari, honey, sesame oil, and grated ginger. Add the cubed salmon, tossing to coat evenly, and spread onto a parchment-lined baking sheet.

Bake the salmon for 8 to 10 minutes until flaky, tender, and caramelized around the edges.

Lightly brush both sides of each nori half with neutral cooking oil. Drape each piece over an upside-down muffin tin or between wire racks to shape into taco shells. Bake at 180 °C (160 °C fan / 177 °C) for 4 to 6 minutes until crisp and rigid.

Spoon a couple of tablespoons of seasoned sushi rice into the base of each crispy nori shell. Top with cucumber matchsticks, diced avocado, and warm roasted salmon chunks.

Drizzle the assembled tacos generously with spicy mayonnaise, then garnish with sliced scallions and toasted sesame seeds. Serve immediately.