To make the teriyaki stir fry sauce: Mix soy sauce, chicken stock, rice vinegar, sesame oil, honey, ginger, garlic and cornstarch in a bowl and whisk until fully combined. Alternatively, you can put it in a jar and give it a vigorous shake.
Pre-heat the oven to 425 degrees. Line a baking sheet with parchment paper. Add broccoli florets to the baking sheet.
Drizzle them with 2-tablepoons olive oil and sprinkle them lightly with salt and pepper. Using your clean hands (or 2 spoons), gently toss them to make sure that each floret is coated with oil.
Let it roast for 14-15 minutes or they turn golden brown. Set aside.
Meanwhile, place a wok (or a 10-inch cast iron skillet) on medium high heat. Add in the remaining 2 tablespoons of oil.
When the pan and oil are sizzling hot, add in the chicken and sauté for 5-6 minutes, stirring frequently.
Give the stir-fry sauce a quick stir/shake and pour it into the pan.
Bring the mixture to a boil and let it simmer for 3-5 minutes. You will see it will start to thicken and become glossy.
Once the chicken is fully cooked through, remove it from the heat.
Place a cup of cooked white or quinoa, 4-5 roasted broccoli florets, and stir-fry chicken in each bowl.
Garnish them with chopped scallions, cilantro, sesame seeds, and if preferred, chopped peanuts.