Cut the onion in half. Slice one half thinly and finely chop the other half. Microwave the chopped onion in a heatproof container at 600W for 1 minute.

In a bowl, soak breadcrumbs in milk. Add ground pork, chopped onion, egg, salt, and pepper. Mix well until sticky. Shape into bite-sized balls.

Heat salad oil in a frying pan over medium heat. Add the meatballs and cook while rolling them until browned. Add sliced onion and stir until coated with oil.