In a small bowl, mix together soy sauce, honey, rice vinegar, sesame oil, garlic, and ginger to create the teriyaki sauce. If using cornstarch, mix it with water to form a slurry and set aside.
Heat a large pan or skillet over medium-high heat. Add a small amount of oil and cook the chicken slices for 4-5 minutes until they are browned and cooked through. Remove the chicken from the pan and set aside.
In the same pan, add a little more oil if needed and sauté the broccoli florets for 3-4 minutes until they become tender but still crisp.
Add the cooked chicken back into the pan with the broccoli. Pour the teriyaki sauce over the chicken and broccoli mixture, stirring to coat everything evenly.
If you’re using the cornstarch slurry, add it to the pan and stir until the sauce thickens, about 1-2 minutes.
Once the sauce has thickened and everything is well combined, remove from heat. Garnish with sesame seeds if desired.
Serve the teriyaki chicken and broccoli over a bed of rice. Enjoy!