Chop the cabbage and king oyster mushrooms into small pieces.
Finely dice the carrot and onion as well.
Heat cooking oil in a pan over medium heat.
Add the onion and carrot first and stir-fry them.
Add the cabbage and king oyster mushrooms, and stir-fry together.
Add the rice and mix well with the ingredients while stir-frying.
Season with salt, pepper, and soy sauce to taste.
Mix everything thoroughly until well combined and it's ready to serve.