After watching a friend make this, I tried it myself. It is quite simple and good. I cooked the potatoes until completely soft, which was longer than she did, because I had some stomach problems when I did not cook them fully.
Take some potatoes and peel them. Slice them into matchstick-sized pieces, then boil them until just barely cooked. Drain, rinse with cold water and set aside.
Mince some garlic and put it in a bowl, along with spices such as: chilli peppers, cayenne pepper, cumin powder, and five-spice powder. Heat some oil to just below bubbling, then pour it over the spices. While it is still cooking the spices, add in a pinch of sugar.
Next add some soy sauce, salt, and vinegar to the spice mixture. Add the spiced oil to the cooked potatoes and mix. Add some spring onion. You can also add boiled and cooled mu-err mushroom (black fungus) for a little variety.