Spread cooked rice onto a parchment-lined tray and press into a thin layer.
Refrigerate at least 1 hour (this helps it crisp better).
Heat avocado oil in a large skillet over medium-high.
Break rice into rough chunks and press into pan.
Cook undisturbed for 3–4 minutes until deeply golden.
Flip and crisp the other side.
Remove and let cool slightly — it will crisp more as it sits.
In a bowl, gently mix: diced tuna, mayo, soy sauce, sesame oil, lime juice and keep chilled until ready to assemble.
In a large bowl combine: crispy rice, cucumber, carrots, green onions, avocado and top with spicy tuna.
Drizzle lightly with soy-sesame dressing.
Sprinkle sesame seeds and jalapeño.