Mix chicken breast pieces with baking soda and let sit for 20 minutes.
Rinse baking soda off the chicken and then pat dry with paper towels.
In a bowl, combine the rinsed chicken breast with 2 teaspoon soy sauce (tamari for gluten-free) and 2 teaspoon tapioca starch and mix well. Set aside.
In a measuring cup, combine the chicken broth, oyster sauce, soy sauce (tamari), honey, sesame oil, and white pepper. Mix well and set aside.
Bring water to a boil in a medium sized pot and parboil broccoli for 2 minutes. Drain and set aside.
Heat wok or frying pan over medium-high heat. Add 2 tbs light olive oil.
Saute garlic, ginger and onions until fragrant, about 1 minute. Add chicken.
Saute chicken until half-done, about 1 minute. Add sauce and broccoli. Mix well.
Cook for 2 minutes to heat through. Add chopped green onions, if desired.
There are other versions of velveting chicken, such as using a mixture of egg whites and cornstarch, and then given the chicken a pre-cook before tossing into your stirfry. I find using baking soda is so much simpler, and I don't have to fuss with having to separate eggs, etc.
It is important to rinse the baking soda off the chicken so you don't have the baking soda taste in your dish.
You could use chicken thigh meat, which is more tender than breast meat to begin with. In this case, you could probably skip the velveting/baking soda step and go straight to marinating the meat after cutting into bite-sized pieces. That being said, velveting thigh meat won't hurt it.
You can substitute the broccoli with other vegetables like cauliflower, sugar snap peas, asparagus, etc. I would still parboil them for 1-2 minutes before tossing into the pan.
Throw in some roasted cashews at the same time as the green onions at the end for a Cashew Chicken variation.
I also like tossing some tofu puffs into the pan at the same time as the sauce and having them soak up some of the delicious gravy!