Drain away the oil from the wok to remove any debris from the flour. Return to the heat. If needed add a tiny dash of oil to the wok then add the white onions and carrots, (some takeaways don't add carrots to this dish, so adapt to what you prefer). Fry quickly for around 2 minutes whilst moving it around the wok. Next add in the spring onion and chillies and garlic. Toss and fry it in the pan until fragrant.