In a mixing bowl, combine sliced chicken with water, oyster sauce, cornstarch, and vegetable oil. Massage the marinade into the chicken and let it sit for about 10 minutes.

In a separate bowl, mix warm low sodium chicken stock, sugar, soy sauce, dark soy sauce, oyster sauce, sesame oil, and white pepper until well blended. Set it aside.

Bring a large pot of water to a rolling boil. Blanch the broccoli florets for 1-2 minutes. Drain and set aside.

Heat a wok over high heat and add a splash of vegetable oil. Sear the marinated chicken for about 3 minutes until almost fully cooked. Remove and set aside.

Lower the heat and add garlic and ginger to the wok. Stir for 5 seconds until aromatic, then pour in the reserved sauce mixture and deglaze the wok.

Incorporate the cornstarch slurry into the sauce while stirring until it thickens, about 10-15 seconds.

Return the cooked chicken and its juices back to the wok. Add the blanched broccoli and stir-fry for a few minutes until well coated.

Serve immediately over steamed rice for a satisfying meal.