Prepare the main ingredients: slice the onion and carrot, chop the green onion and green chili, and tear the oyster mushrooms into bite-sized pieces.

Mix 1 tbsp cornstarch with 2 tbsp water to create cornstarch slurry. Stir well before using.

Combine all sauce ingredients in a bowl to make the sauce.

Heat oil in a pan over low heat and sauté the green onion to create green onion oil.

Add the prepared vegetables (onion, carrot, green chili, and oyster mushrooms) to the pan and stir-fry until softened.

Pour the sauce over the vegetables and stir-fry briefly.

Add a small amount of water to the pan and simmer the mixture.

Add the cornstarch slurry to the pan and stir until the sauce thickens.

Simmer the sauce until the flavors meld together.

Prepare a bowl of rice for serving.