Slice the potatoes into thick pieces and dice the onion into squares.

Dissolve 1 tbsp salt in a bowl of water and soak the potato slices for 10 minutes to remove starch.

Mix soy sauce, gochujang, sugar, minced garlic, and chili powder in a bowl until the gochujang is fully dissolved.

Heat a lightly oiled pot and sauté the potatoes and onions until coated and slightly cooked.

Add the prepared seasoning mixture and stir-fry. Pour in 100 ml water and simmer on medium-low heat until the potatoes are tender.