Slice the beef thinly across the grain into bite-size strips, cutting against the visible muscle fibres. Combine in a bowl with the light soy sauce, Shaoxing wine, oyster sauce, cornstarch, sugar, white pepper, and 1 tsp neutral oil, mixing until every strip is lightly and evenly coated. Let it stand for 20–30 minutes while you prepare everything else, but not for hours, since this is a short stir-fry marinade, not a braise. The strips should look genuinely glossy and lightly coated rather than sitting in liquid. That thin cornstarch coating is what shields the beef from the wok’s fierce heat, keeping it juicy instead of dry.

Gently separate the fresh rice noodles by hand into loose ribbons. If they are cold and firm, let them come closer to room temperature first. If refrigerated noodles are stuck together, warm them very briefly so they loosen, but do not soak them heavily or they may break, and do not rinse them unless absolutely necessary. The ribbons should lift apart freely, with no clumps. That genuinely careful separation now is what protects the noodles later, since the stir-fry moves far too fast to untangle them in the wok.

In a small bowl, combine the light soy sauce, dark soy sauce, oyster sauce, Shaoxing wine, sugar, white pepper, and sesame oil, stirring until the sugar dissolves. Set the bowl beside the stove where it can be poured in one smooth motion. The sauce should look dark, glossy, and deliberately modest in volume, because chow fun should finish glossy, not wet. That dark soy is what supplies the classic brown colour and slightly caramelised look the finished noodles are known for.

Wash the bean sprouts and dry them well. Cut the Chinese chives into 5–6cm lengths, the scallions into 4–5cm batons, and slice the garlic thinly. Keep each ingredient in its own pile within arm’s reach of the stove, with the extra sliced scallion set aside for garnish if wanted. Keep the vegetables simple and classical, with no broccoli, carrots, peppers, or onions. Drying the sprouts genuinely thoroughly is what stops stray water from cooling the wok and steaming the noodles when the final toss begins.

Heat a wok or large heavy pan over very high heat until just smoking. Add 1 tbsp of the stir-fry oil and swirl to coat. Add the beef in a single layer and sear for about 45–60 seconds per side, just until browned at the edges and mostly cooked, then remove it immediately to a plate. If the pan is small, cook the beef in 2 batches. The beef should not be cooked fully through at this stage. That brief sear is what genuinely builds browned flavour while leaving the strips tender enough to finish later without toughening.

Reheat the wok over high heat and add the remaining 1–2 tbsp oil. Add the garlic and scallion batons and stir-fry for 10–15 seconds until fragrant. Add the noodles and spread them across the wok surface, letting them sit for 30–45 seconds to pick up heat and a few lightly charred spots before tossing. Pour the sauce around the edge of the wok, then toss and lift carefully for 1–2 minutes until the noodles are evenly coloured. Return the beef, then add the bean sprouts and chives and toss for 30–45 seconds, just until the sprouts wilt slightly and the chives soften. Remove immediately. On a home stove, work in 2 smaller batches, dividing the noodles, sauce, beef, and vegetables equally. That speed and restraint is what keeps the noodles charred and silky rather than mushy.

Divide the chow fun between 4 bowls or plates and serve immediately, garnishing with a little extra sliced scallion if wanted. The finished dish should show glossy broad noodles, visible dark soy colour, a few wok-charred patches, tender beef slices distributed prominently, crunchy bean sprouts, and green chive and scallion contrast. Serving it straight from the wok is what genuinely captures the noodles at their silkiest and the sprouts at their crispest, before steam softens either.