Shred the cabbage thinly and wash it thoroughly in water, changing the water 3–4 times.

Drain the cabbage using a colander and set aside.

Prepare the canned tuna, egg, chopped green onion, and diced carrot.

Heat a frying pan and add the shredded cabbage, canned tuna (including its oil), and 1 tbsp olive oil.

Stir-fry the cabbage until it softens and wilts.

Add 0.4 tbsp tuna sauce to the pan and mix well.

Shape the stir-fried mixture into a donut shape in the pan and crack an egg into the center.

Cover the pan and cook on low heat for 2 minutes until the egg white sets.

Place cooked rice in a bowl and carefully layer the stir-fried cabbage and tuna mixture on top.