Prepare the sauce by dissolving the stock cube, salt, sugar, and white pepper in boiling water. Stir in soy sauce and set aside.
Heat vegetable oil in a large pan or wok. Add minced beef and curry powder. Cook until browned and crispy in places. Remove and set aside.
Add more oil if needed. Stir-fry the white part of the spring onions until fragrant, then add bean sprouts and cook for 1-2 minutes.
Rehydrate noodles according to packet instructions. Rinse in a colander under cold water immediately after draining, and again before adding to the wok to loosen. Add to the pan with sesame oil and the sauce. Toss well to coat.
Return the cooked beef to the pan along with green spring onions and hoisin sauce. Toss again until hot and combined.
