Heat oil in a large pan over medium heat, and add green onion and onion. Cook until fragrant. Add carrot, spam, and mushroom, and cook for 3-4 minutes.

Add rice, soy sauce, and ketchup and mix to combine, ensuring all grains are evenly coated. Add to a small bowl and press down to shape the rice.

Combine eggs, milk, and salt in a bowl. Heat oil in a non-stick skillet over medium heat, and pour in the egg mixture. Lightly scramble for a few seconds until the eggs are about 80% cooked through, and remove from heat.

Place a large plate over the bowl of rice, hold it in the center, and flip carefully to plate the rice in a dome shape. Cover the rice with the egg omelette, and garnish with ketchup and parsley to serve.