Cut the chicken into 1-inch cubes.
In a bowl, combine 1 tablespoon arrowroot (or cornstarch), garlic powder, onion powder, 1/4 teaspoon salt, and 1/4 teaspoon black pepper; toss with the chicken so pieces are lightly coated.
Heat 1 tablespoon olive oil in a large skillet over medium-high heat. Add the chicken in an even layer and cook, stirring as needed, until lightly browned and cooked through, about 4 to 5 minutes. Transfer chicken to a plate.
Add the remaining 1 tablespoon olive oil to the hot skillet. Add the trimmed green beans, season with a pinch of salt and pepper, and sauté until they develop a little char and are tender-crisp, about 6 minutes.
While the beans cook, whisk together the chicken broth, soy sauce, honey, minced garlic, and grated ginger in a small bowl.
In a separate small bowl, mix 2 teaspoons arrowroot (or cornstarch) with 2 teaspoons water until smooth to make a slurry; set aside.
Add the cooked chicken back to the skillet with the green beans. Pour the honey-garlic sauce over everything, then stir in the arrowroot slurry. Bring to a boil, then reduce heat and simmer until the sauce thickens and coats the chicken and beans.
Remove from heat, sprinkle with chopped green onions and sesame seeds if using, and serve.
