Prepare all ingredients by washing and cutting them as described.

Cut the potato into quarters and slice thinly.

Slice the onion into thick strips.

Slice the green onion and green chili diagonally.

In a pot, add canned tuna and sliced potatoes. Pour water until ingredients are slightly submerged.

Add red pepper flakes, sugar, soy sauce, and minced garlic. Bring to a boil.

Once potatoes are halfway cooked, add onion, green onion, and green chili. Continue boiling.