Place the peeled and cut potato pieces in a large pot of boiling water.

Add ½ teaspoon of salt to the boiling water and cook the potatoes until they are tender.

Drain the cooked potatoes and let them cool for a few minutes.

Once cooled, mash the potatoes until smooth using a potato masher or a fork.

In a mixing bowl, combine the mashed potatoes and potato starch.

Gradually add warm water to the mixture while kneading it with your hands.

Continue kneading until a dough-like consistency is achieved.

Shape the dough into a ball and let it rest for about 10 minutes.

This step requires some patience and precision, but the end result is well worth the effort!

Divide the rested dough into smaller portions for easier handling.

Roll out each portion into a thin sheet using a rolling pin.

Dust the sheet with potato starch to prevent sticking.

Using a sharp knife or a pasta roller, cut the sheet into long, thin noodles.

Repeat this process with the remaining dough portions until all the potato noodles are formed.

In a small bowl, combine soy sauce, Chinese black vinegar, gochugaru (or Chinese chili powder), sugar, and salt.

Mix well until all the ingredients are thoroughly combined.

In a separate pan, heat the oil over medium heat.

Add the minced garlic and sliced green onion to the pan and cook until fragrant.

Reduce the heat to low and add the prepared sauce mixture to the pan.

Stir the sauce continuously to prevent burning and cook for about 2-3 minutes.

Remove the pan from heat and set aside.

Bring a large pot of water to a boil.

Add the prepared potato noodles to the boiling water and cook for about 3-4 minutes, or until they are firm but tender.

Drain the cooked noodles and rinse them under cold water to remove excess starch.

Gently toss the noodles with a small amount of oil to prevent sticking.

Transfer the cooked potato noodles to a large mixing bowl.

Pour the prepared spicy chili oil sauce over the noodles.

Using tongs or chopsticks, gently toss the noodles until they are fully coated with the sauce.

Add the chopped cilantro to the bowl and give it a final toss.