Mix 2 teaspoons of dark soy sauce, 1½ tablespoons of oyster sauce, 1 tablespoon of light soy sauce, 2 teaspoons of white vinegar, and 2 teaspoons of sugar.
Cut 4 stalks of Chinese broccoli into 3in / 7.5cm pieces, separating leaves and stems. Split thick stems lengthwise. Prepare 200g of dried wide rice noodles according to the package directions; drain just before cooking.
Heat 1 tablespoon of vegetable oil in a large wok over high heat. Fry 2 garlic cloves, minced, for 15 seconds. Add 150g of boneless chicken thigh, thinly sliced, and cook until mostly opaque.
Add the broccoli stems, then the leaves. Stir-fry until the stems are tender, leaves wilted and chicken cooked through. Push aside and scramble 1 large egg in the pan. Transfer everything to a plate.
Heat 2 tablespoons of extra vegetable oil in the wok. Add the noodles and sauce; toss sparingly for 1-1½ minutes, until lightly caramelized.
Return the chicken mixture and toss briefly. Serve immediately.
