Prepare oatmeal, tuna, onion, and carrot.
Finely chop the onion and carrot.
Add tuna and chopped vegetables to a pot and stir-fry.
Add oatmeal and stir-fry, then pour in water.
Simmer over low heat, stirring constantly.
When the porridge thickens, season with salt.
Transfer the finished porridge to a bowl.