Heat the oil in a 10- to 12-inch nonstick or seasoned cast iron skillet over high heat. Add the garlic, ginger, chili flakes, and the chicken strips. Cook, stirring often, for 3-5 minutes until the chicken is cooked through (check the center of one of the strips).
In a small bowl, whisk together the broth, fish sauce, and cornstarch until well-combined. Pour the sauce into the skillet and while stirring, bring to a boil. Remove from heat and add the basil leaves and toss. Taste, and add salt if needed. Serve hot.