Finely chop the onion, carrot, bell pepper, and mushroom.

Heat a pan with a little oil and stir-fry the onion, followed by carrot, bell pepper, and mushroom. Season with salt and pepper.

Mix the cooked rice with the stir-fried vegetables in a bowl until evenly combined.

Blanch the chives in boiling water until soft. Use long chives for tying.

Lightly pan-fry the ham slices until just cooked. Avoid overcooking to prevent them from shrinking.

Shape the rice mixture into small balls, adjusting the size to fit the ham slices.

Wrap each rice ball with a slice of ham, leaving a small gap to show the rice.