Soak the seaweed in cold water for 5 minutes, then drain.
Rinse the oatmeal with water and set aside.
Add sesame oil to a pot and stir-fry the seaweed for 1 minute.
Add the tuna and stir-fry together.
Pour in water and bring to a boil.
When the water boils, add the oatmeal and simmer, stirring, for 5-8 minutes.
Season with salt to taste and finish.