1. Heat vegetable oil in a wok over high heat and stir-fry garlic, onion and ginger for 2 minutes or until onion is starting to brown. Toss through chillies.
2. Add pork and stir-fry until just cooked. Add fish sauce, oyster sauce and sugar. Stir-fry for another minute to coat everything in the sauce.
3. Serve with steamed rice.