In a small glass bowl whisk all Teriyaki sauce ingredients together really well; set aside.
Heat a large skillet over medium-high heat, then add oil. Add in the beans and 2 Tablespoons of water. Stir.
Cover and cook for 3-4 minutes, then stir again and continue to cook until they are done to your liking (I prefer them on the crunchy side "tender crisp" and still very green).
Drizzle your homemade teriyaki sauce over the beans and cook stirring until sauce thickens and beans are nicely coated for just a minute or two.
Sprinkle with sesame seeds before serving and enjoy immediately!