Combine the oyster sauce, soy sauce, sugar and water in a small bowl and stir to combine.
Heat 1 tbsp oil in a large frying pan or wok over a medium heat. Add the onion and stir fry for 3-4 minutes until starting to soften. Add the garlic and chillies and cook for another minute or two.
Increase the heat to medium high and add the pork mince, drizzling in a little more oil if needed. Cook for a few minutes until browned, breaking up the meat as you go.
Stir in the green beans then add the sauce and stir fry for a minute or two. Once the beans are cooked, stir through the basil. Turn off the heat,taste and add an extra splash of soy if needed.
In a separate pan add a drizzle of oil and fry the two eggs to your liking.
Serve the pork with rice, topped with a fried egg. Drizzle over some chilli oil or sweet soy sauce if you like.