Thinly slice 1/2 onion and prepare 1 tablespoon of chopped onion.

Mix 1 tablespoon of chopped onion, 2 tablespoons of mayonnaise, and 1 can of tuna to make tuna mayo.

In a pan, combine 2 tablespoons of soy sauce, 2 tablespoons of corn syrup, and 2 tablespoons of mirin. Heat until bubbling, then add sliced onion. Cook until onion turns translucent.

In another pan, lightly oil and scramble 2 eggs using chopsticks.

Place 1 bowl of cooked rice in a serving dish and top with scrambled eggs.

Top the eggs with cooked onion, tuna mayo, and chopped green onion.