Place the sliced chicken in a medium-sized bowl. Add soy sauce, garlic powder, and onion powder. Toss to combine. Add cornstarch and stir until chicken is coated. Set aside.

In a small bowl, stir together chicken stock, brown sugar, soy sauce, oyster sauce, rice wine vinegar, and cornstarch. Set aside.

In a wok or large skillet over medium-high heat, add 1 tablespoon of oil. Once hot, add the chicken to the pan, flattening it into a single layer. Let it sear for 30 seconds to a minute. Toss chicken until cooked through, about 5-6 minutes. Set aside on a plate.

Add another tablespoon of oil to the same pan and sear the mushrooms, stirring constantly, until they begin to soften, about 2 minutes. Place mushrooms on the plate with the chicken.

Add the remaining oil and sear/cook the zucchini, stirring constantly, until tender-crisp, about 2-3 minutes. Place the zucchini on the plate with the chicken and mushrooms.

Add ginger and garlic to the skillet, and cook until fragrant, about 30 seconds. Add the sauce, stir, and as soon as it starts to bubble, add all the ingredients back to the pan and coat in the sauce.

Let it simmer for 1-2 minutes until warmed through and the sauce is thickened.

Serve immediately with rice or lo mein. Garnish with sesame seeds and green onions, if desired.