Toss chicken, cornstarch, red pepper flakes, a pinch of salt, and 1 tbsp soy sauce in a medium bowl
Stir together vinegar, wine, and remaining 2 tbsp soy sauce in a small bowl; make sure all other ingredients are prepped and ready to cook
Heat 1 tbsp oil in large skilled (not nonstick) over high heat. When oil is shimmering, add scallions and ginger; cook, tossing, until scallions and browned and softened, about 2 minutes. Add green beans and a pinch of salt and cook, tossing often, until green beans are crisp-tender, about 4 minutes. Transfer green bean mixture to medium bowl
Heat remaining 1 tbsp oil in same skillet over high. When oil is shimmering, add chicken mixture and arrange slices in a single layer. Cook, undisturbed, until chicken is browned and caramelized on the first side, about 1 minute. Toss and continue to cook until chicken is cooked through, about 1-2 more minutes. Pour in wine mixture and green bean mixture and cook, tossing briskly, until sauce is thickened and all ingredients are coated, about 30 seconds. Remove from heat and taste, seasoning with salt and pepper to taste
Serve with rice and garnishes