Peel and dice the potato into small cubes.

Dice the carrot, onion, and green chilies into similar-sized cubes.

Drain the potato and pat dry with a kitchen towel.

Heat a pan with a small amount of cooking oil and stir-fry the potato until it becomes translucent.

Add the diced carrot and stir-fry until it also becomes translucent.

Add the diced onion and green chilies, and stir-fry until the onion turns translucent.

Add the drained tuna and mix well with the vegetables.

Add 2 tbsp gochujang, 2 tbsp oyster sauce, 1/2 tbsp chili powder, 1 tbsp sugar, and 1 cup water.

Stir the mixture well and let it simmer on medium-low heat until the sauce thickens.