Slice sweet potato into thin rounds, and cut into matchsticks. Soak in water in a large bowl and let sit for 10 minutes. Strain water and remove moisture as much as possible.
Heat a frying-pan with oil at medium heat, add potato, and stir-fry for a couple of minutes. Add water, cover, turn down heat to medium low, and cook for 2-3 minutes.
Add the rest of the ingredients and stir gently so that potato is not going to break into small pieces. Once all the liquid is gone, add sesame seeds, and remove from heat.
