I've had a very similar recipe and this is a GREAT appetizer or light lunch. Add a little rice, or wrap it in seaweed or lettuce and you're good to go.
Cube up the tuna (skipjack, bonito, Yellow Fin Tuna, Blue Fin Tuna) into 1/2 inch cubes, add some soy sauce, sambal oelek, hawaiian sea salt, diced green onion, dice maui sweet onion, brown sugar, sesame oil, fresh ginger, fresh seaweeed, and some toasted sesame seeds. I add some dice peeled cucumber sometimes.
Mix it up and good to go. Serve with some dice avocado and tortilla chi