Prepare the potatoes and onion.

Cut the onion into bite-sized pieces.

Cut the potatoes into bite-sized pieces and soak them in water for 2-3 minutes. Drain the water.

Drain the water from the potatoes completely.

Add 1 cup water, 4 tbsp soy sauce, 1 tbsp sugar, 1 tbsp corn syrup, and 1 tbsp oyster sauce to the potatoes and simmer. Avoid stirring too often.

Check if the potatoes are cooked and the sauce has thickened.

Add the onion to the pot and continue cooking.