In a small bowl, whisk together the soy sauce, chicken broth, cornstarch, brown sugar, sesame oil, and red pepper flakes until smooth.
Heat 1 tablespoon of vegetable oil in a wok or large skillet over medium-high heat.
Add the green beans to the skillet and stir-fry for 3 to 4 minutes until they are tender-crisp and slightly charred, then remove them and set aside.
Add the remaining 1 tablespoon of oil to the same skillet and increase heat to high.
Add the chicken strips in a single layer and sear for 2-3 minutes per side until browned and cooked through.
Add the minced garlic and ginger to the chicken and sauté for 30 seconds until fragrant.
Return the green beans to the skillet.
Whisk the sauce mixture once more and pour it over the chicken and beans.
Toss constantly for 1 to 2 minutes until the sauce has thickened and coats the ingredients glaze-like.
Serve immediately over steamed rice or noodles.