Cook the chow mein noodles according to the package directions. Drain them well and set them aside.
In a small bowl, whisk together the chicken broth, soy sauce, oyster sauce, cornstarch, sugar, ginger, and white pepper. Set this aside.
Heat the vegetable oil in a large skillet or wok over medium-high heat. Add the chicken (or your chosen protein) and cook until it's fully cooked through and lightly browned. Remove the chicken from the skillet and set it aside.
Add the carrots, celery, bell pepper, and onion to the skillet and stir-fry for about 3-5 minutes, until they're slightly softened but still have a bit of crunch. Add the garlic and cook for another minute, until fragrant.
Add the shredded cabbage to the skillet and stir-fry for another 2-3 minutes, until it's slightly wilted.
Return the cooked chicken to the skillet. Add the cooked noodles and the sauce mixture. Toss everything together until the noodles and vegetables are evenly coated with the sauce, and the sauce has thickened.
Serve immediately, garnished with sliced green onions and sesame seeds, if desired.