In a small bowl, whisk together Worcestershire sauce, oyster sauce, soy sauce, ketchup, and sugar to create the yakisoba sauce.
Heat one tablespoon of vegetable oil in a large wok or skillet over medium-high heat.
Add the chicken slices and cook until browned and cooked through, then remove and set aside.
Add the remaining tablespoon of oil to the wok, then add the onion, carrot, and cabbage. Stir-fry for 4 minutes until the vegetables are slightly softened.
Add the garlic and stir-fry for another 30 seconds.
Add the yakisoba noodles to the wok, adding a tablespoon of water if necessary to help separate the strands.
Return the chicken to the wok and pour the sauce over the noodles and vegetables.
Toss everything together continuously for 3 minutes until the sauce evenly coats all ingredients and is slightly caramelized.
Serve immediately, garnished with pickled red ginger and aonori.