Cut the fish cake and onion into bite-sized pieces.
Mix all the sauce ingredients together to make the seasoning sauce.
Tip.If the sugar doesn't dissolve easily, add 1 T of water to make mixing easier.
Heat about 4 T of cooking oil in a pan and sauté the minced garlic until fragrant.
Once the garlic smells fragrant, add the fish cake and stir-fry over medium heat for about 2 minutes.
Add the onion and the prepared sauce all at once, then stir-fry quickly over medium-high heat for about 3 minutes.
Tip.Simmering the sauce too long can burn it quickly because of the corn syrup, so the key is to stir-fry briefly over medium-high heat.
Finish by sprinkling toasted sesame seeds on top, and it's ready to serve.