Cook the noodles:
Boil the chow mein noodles according to package instructions. Drain and toss with 1 tbsp sesame oil to prevent sticking. Set aside.
Make the sauce:
In a small bowl, whisk together the soy sauce, oyster sauce, hoisin sauce, sugar, sesame oil, and broth. Set aside.
Prepare the stir-fry:
Heat 2 tbsp of vegetable oil in a wok or large skillet over medium-high heat. Add the minced garlic and sliced onion, stirring until fragrant.
Cook the vegetables:
Add the shredded cabbage, carrots, and bell peppers. Stir-fry for 2–3 minutes, or until the vegetables are slightly softened but still crisp.
Add the protein and noodles:
Stir in your cooked protein of choice and the pre-cooked noodles. Toss everything together.
Pour in the sauce:
Add the sauce mixture to the wok. Toss everything to coat the noodles and veggies evenly. Cook for 2–3 minutes until heated through.
Garnish and serve:
Remove from heat, sprinkle with chopped green onions, and serve hot. Enjoy your homemade chow mein!