Prepare the beef by removing excess blood. Wash and chop the spinach, and dice the onion.

Scramble the egg in a pan using chopsticks until partially cooked, then push it to one side.

Sauté the onion in the same pan until translucent.

Add the prepared beef to the pan and stir-fry with the onion.

Combine the egg, onion, and beef, stir-frying them together on high heat.

Add the spinach to the pan and stir-fry briefly.

Season with oyster sauce and plum syrup, or substitute soy sauce if preferred.

Sprinkle sesame seeds over the mixture and stir well.