Tip the rice into a bowl and mix in the spring onions, soy sauce, mayo and sriracha, if using. Fold in the salmon, keeping it flaked or mashing it in with the rice, as you prefer. Divide between two reusable containers. Pack each one into a lunchbox with a pack of seaweed thins, and half each of the avocado and cucumber.

To eat, spoon the rice onto a seaweed thin, top with avocado and cucumber, then loosely roll up.