Drain the noodles and brown the mushrooms

Follow the chow mein noodle package for cooking and any rinsing instruction, then drain thoroughly. Excess noodle water would join the measured broth-based sauce, making its final consistency harder to judge. Whisk the sauce in advance and keep it within reach of the stove.

Cook the chicken first and move it to a clean bowl. Give the mushrooms their own stage afterward, waiting for their released liquid to evaporate and their surfaces to begin browning before adding the cabbage, carrot and garlic. That sequence is especially useful in a pan already holding several vegetables and noodles.

Stir the sauce again before it meets the noodles

Cornstarch can settle while the noodles and stir-fry components cook. Reach the bottom of the sauce bowl with the whisk before pouring it over the returned chicken and drained noodles.

Lift and turn the noodles so sauce reaches the bottom of the pan as well as coating the top strands. Finish when it has thickened around the chicken and vegetables, then fold in the scallions. Oyster sauce contains shellfish; the mushroom addition does not make this a shellfish-free dish.