In a bowl, toss the chicken strips with garlic powder, salt, pepper, and 1 tablespoon of cornstarch until evenly coated. Set aside.

Warm a large skillet or wok over medium heat and melt 1 tablespoon of butter. Add the green beans and cook for about 5 minutes, stirring frequently, until they begin to soften and brown.

Add the bell pepper strips and cook for another 3 minutes until tender. Transfer the vegetables to a plate and set aside.

Add the remaining tablespoon of butter and the sesame oil to the pan. Add the chicken and cook, turning as needed, until browned and cooked through. Transfer the chicken to the plate with the vegetables.

In a small bowl, whisk together the chicken broth, honey, sugar, rice vinegar, soy sauce, sesame oil, and red pepper flakes.

Return the pan to medium heat. Add the minced garlic and ginger and cook for about 30 seconds until fragrant.

Pour most of the sauce into the pan, reserving about 2 tablespoons. Let it simmer for about 3 minutes.

Mix the reserved sauce with the remaining 2 tablespoons of cornstarch. Stir this mixture into the pan and cook until the sauce thickens.

Return the chicken and vegetables to the pan and toss to coat everything evenly.

Sprinkle sesame seeds over the top and serve warm.