Preheat your oven to 220°C (425°F). Spread cooled rice on a lined baking tray and drizzle with tamari, sesame oil, and olive oil. Bake for 40–50 minutes, stirring every 15 minutes to ensure even crisping.
In a medium bowl, whisk together mayonnaise, tamari, rice wine vinegar, sesame oil, honey, and sriracha. Set aside to let the flavors meld while the rice bakes.
In a large bowl, combine tuna, cucumbers, edamame, avocado, spring onions, and crispy rice. Pour over the dressing and gently toss to coat everything evenly.
Sprinkle with black sesame seeds, chilli crisp, and sliced jalapeños. Serve immediately for the best texture, letting everyone enjoy the contrast of creamy avocado and crunchy rice.