Dice onions, pork, potatoes, and carrots.
Heat cooking oil in a pan and stir-fry the pork.
Add onions, potatoes, and carrots, and stir-fry together.
Once the vegetables are cooked, add the Jajang sauce and mix well.
Pour in 200ml of water and simmer over medium heat.
Adjust the thickness with starch water.
Spoon the Jajang sauce over rice to finish.