Cook the egg noodles in boiling water until tender but not mushy.
Drain the noodles and dump in a bowl of iced water to immediately stop the cooking.
Drain the noodles once more and set aside.
Heat the cooking oil in a wok.
Over high heat, stir fry the chicken fillet slices until no longer pink.
Add the shrimps to the chicken, and drizzle in the soy sauce and rice wine.
Stir fry for a minute or until the shrimps are almost cooked through.
Add the sliced onion, garlic, julienned carrot and stems of the Chinese broccoli.
Sprinkle in two generous pinches of salt and about a quarter teaspoon of pepper.
Stir fry for another minute.
Add the leaves of the Chinese broccoli and stir fry for half a minute.
Add the drained noodles.
Pour in the oyster sauce and hoisin sauce.
Continue stir frying until the noodles are heated through and the sauces evenly distributed.
Off the heat, taste the chicken and shrimp chow mein, and add more salt or pepper, or both, if needed.
Drizzle in the sesame seed oil and give the chow mein a final toss.
Serve the chicken and shrimp chow mein immediately.