Soak the wide flat rice noodles in warm water until pliable, about 30 minutes. Drain and set aside.
Thinly slice the chicken thighs and place them in a bowl. Set aside while prepping other ingredients.
Mix dark soy sauce, light soy sauce, oyster sauce, and sugar in a small bowl. Stir until well combined.
Heat oil in a wok over medium-high heat. Add the chicken and stir-fry until lightly cooked. Add the noodles and broccoli, stir-frying together for 2–3 minutes.
Pour the sauce over the stir-fry and toss everything together until the noodles are evenly coated and slightly caramelized.
Push the stir-fry to the side, pour in the beaten egg, and scramble until just set. Mix everything together.
Serve hot on a plate, optionally with chili flakes or a side of chili vinegar for extra flavor.
