Slice the chicken against the grain into thin bite-size pieces, no thicker than 1/4”, transfer into a medium-size bowl. Add the marinade ingredients. Stir to mix well. Let sit for 10 minutes while preparing other ingredients.
Combine all the sauce ingredients in a bowl. Stir to mix well. Set aside.
Bring 1/3 cup of water to a boil in a large nonstick skillet or wok over medium-high heat. Add the broccoli and cover. Steam until the broccoli just turns tender and the water evaporates, about 40 to 50 seconds. Transfer the broccoli to a plate.
Wipe the pan with a paper towel held in a pair of tongs if there’s any water left.Add the oil and swirl to coat the bottom. Spread the chicken in the skillet in a single layer. Allow to cook without touching for 30 seconds, or until the bottom side is browned. Flip to cook the other side for a few seconds. Stir and cook until the surface is lightly charred and the inside is still pink.*
Add the garlic and ginger. Stir a few times to release the flavor and fragrance.
Return the broccoli to the pan. Stir the sauce again to dissolve the cornstarch completely and pour it into the skillet. Cook and stir until the sauce thickens, about 1 minute. Transfer everything to a plate immediately.
Serve hot with steamed rice .
Notes
I multiplied the recipe x3 and therefore, used 3 pounds of chicken. To do so, I seared it in batches. When the last batch was cooked, I returned all of the chicken to the pan and proceeded with the recipe.