Bring a large pot of water to a rolling boil, drop noodles, cook until al dente (3–5 minutes), then drain and rinse under cool water.

In a small saucepan over medium heat, combine neutral oil and sesame oil until shimmering hot (about 2 minutes).

Reduce heat to low, stir in garlic, dried chili flakes, and optional Sichuan peppercorns; cook gently until garlic turns golden and fragrant (1–2 minutes).

Remove from heat, let spices steep for 5 minutes, then strain oil into a heatproof bowl, discarding solids.

Transfer drained noodles to a serving bowl, pour the aromatic chili oil evenly, stirring to coat each strand.

Add soy sauce, rice vinegar, and sugar; gently toss until noodles glisten and the flavors balance.

Top with sliced scallions, extra chili flakes, or a sprinkle of toasted sesame seeds for color and crunch.