Cook the noodles

• Bring a pot of water to a boil and cook the noodles until tender.
• Drain and rinse briefly, then divide between bowls.

Make the chili oil base

• In a heatproof bowl, combine the chili flakes, minced garlic, sesame seeds and sliced scallion.
• Stir in the soy sauce, rice vinegar, sugar and sesame oil.

Heat the oil

• Heat the neutral oil in a small saucepan until shimmering hot.
• Pour it carefully over the chili mixture so it sizzles.

Toss and serve

• Spoon the chili oil over the noodles and toss well to coat.
• Top with extra scallion and serve immediately.