Bring a large pot of water to a full rolling boil and add the 2g of salt. Add the 400g of fresh Hong Kong-style egg noodles and cook for exactly 2 minutes — fresh egg noodles are thin and cook very quickly, and 2 minutes produces a just-tender noodle with slight resistance remaining. Drain immediately and rinse under cold running water until completely cooled — the cold rinse stops cooking instantly and removes excess surface starch that would cause the thin noodles to clump together into a solid mass within minutes. Toss the rinsed noodles with 5ml of the neutral oil, coating every strand. Spread on a large plate or tray rather than leaving in a bowl — spreading prevents the bottom layer from being compressed and sticking while the top layer dries. Set aside completely ready before the wok is turned on.

In a small bowl, combine the 60ml of light soy sauce, 30ml of oyster sauce, 15ml of dark soy sauce, 45ml of Shaoxing wine, 10g of sugar, 5g of white pepper, and 60ml of chicken stock. Whisk until the sugar is completely dissolved. The four-component soy combination is the specific technique that produces depth and visual colour simultaneously: light soy provides the primary salt and savoury umami throughout the dish; dark soy provides a deeper, slightly molasses-sweet flavour and the characteristic deep brown colour that makes authentic chow mein visually distinct from a pale stir-fry; oyster sauce adds a concentrated sweet-savoury secondary umami layer with more body than soy alone; Shaoxing wine adds the aromatic, slightly fermented grain depth that is the background note in virtually every authentic Chinese stir-fry sauce. In a separate small bowl, combine the 10g of cornstarch with 15ml of water, stirring until completely smooth and lump-free. The slurry is added at the final stage and thickens the sauce from a liquid coating to a glossy, clinging sauce that adheres to every noodle strand. Stir the slurry immediately before using — cornstarch settles rapidly and will be fully separated if not restirred.

Heat the wok over the highest available heat for 2–3 full minutes until a drop of water evaporates immediately and completely on contact with the surface. Add 25ml of the neutral oil and swirl to coat the entire wok surface. When the oil begins to shimmer and the first wisps of smoke appear, add the 500g of chicken strips in a single layer. The chicken must be cut to uniform thinness — approximately 5mm thick, cut across the grain of the thigh meat — so every piece reaches the correct internal temperature at the same time. Leave completely undisturbed for 90 seconds. The undisturbed contact with the smoking surface produces the caramelised, golden crust that contributes savoury depth to both the chicken and the wok's cooking medium — the chicken fat rendered during this sear enriches the surface for subsequent cooking steps. Stir-fry for a further 2–3 minutes, turning the strips occasionally, until golden-brown on most surfaces and just cooked through. Transfer to a plate with all accumulated juices — these juices return to the wok at the combination step and contribute concentrated chicken flavour to the final sauce.

Return the wok to high heat without cleaning it — the chicken fond remains on the surface and will be incorporated into the vegetables. Add the remaining 15ml of neutral oil. Add the julienned ginger and thinly sliced garlic simultaneously. Stir-fry for exactly 20 seconds, moving continuously — at the wok's temperature, thin garlic slices and fine ginger julienne bloom their aromatic compounds explosively within 10 seconds and move toward burning within 30. The 20-second window produces fragrant, slightly cooked aromatics without bitterness. Add the white scallion parts, julienned carrots, and sliced shiitake mushrooms. Stir-fry for 2 minutes, tossing continuously but allowing brief stationary contact with the hot wok surface — the brief contacts produce the slight char at vegetable edges that is the visual and flavour signature of wok cooking. The shiitake will release moisture and then caramelise as the moisture evaporates. Add the napa cabbage and stir-fry for 1 minute until it begins to wilt at the edges while retaining crunch at the centres — napa cabbage at full wilt produces a watery, soft result; the brief 1-minute treatment leaves it tender-crisp. Add the bean sprouts and green scallion parts. Toss for 30 seconds — enough to heat the sprouts through while preserving their crunch completely.

Push all the vegetables to the outer edges of the wok, clearing a space in the centre. Add the remaining 15ml of neutral oil to the centre. Add the cooked, oiled noodles to the oil in the centre well. Spread them out with tongs and leave completely undisturbed for 30 seconds. This 30-second stationary contact with the hot, oiled wok surface is the technique step most responsible for the textural quality of restaurant chow mein — the noodles' exterior surface caramelises very slightly against the wok, producing the characteristic slightly crisped, slightly smoky exterior that is absent from noodles that are simply tossed from the moment of entry. After 30 seconds, toss the noodles together with the vegetables from the outer edges. Return the seared chicken pieces and every drop of the accumulated resting juices to the wok.

Pour the entire prepared sauce mixture over the noodles, chicken, and vegetables. Toss vigorously for 1–2 minutes using a scooping and folding motion — the scooping action lifts the sauce from the bottom of the wok and folds it over the noodles rather than simply stirring, which distributes the sauce more evenly through the full depth of the ingredients. Give the cornstarch slurry an immediate stir to redistribute the settled starch, then drizzle it around the perimeter of the wok rather than pouring it into the centre — the perimeter drizzle allows the slurry to hit the hot wok surface briefly before being incorporated, which initiates the starch gelatinisation faster than cold slurry poured into the centre of the dish. Toss for 30 seconds as the sauce visibly thickens and develops the glossy sheen that coats each noodle strand. Drizzle the 15ml of toasted sesame oil over the finished dish and toss once more to distribute — the sesame oil goes in last because its aromatic compounds are volatile and would largely dissipate if added earlier in the cooking process. Serve immediately.