In a medium bowl, combine sliced chicken thighs with soy sauce, Shaoxing wine (or sherry), and cornstarch. Toss to coat and let sit 15 minutes while you prep everything else.
Whisk all sauce ingredients in a bowl until smooth. Set aside.
Heat 1 tablespoon oil in a large skillet or wok over medium-high heat. Add the green beans and cook, tossing occasionally, until blistered, bright, and just tender for 6 to 7 minutes. Transfer to a plate.
Add 2 tablespoons oil to the pan. Add the chicken in an even layer and cook without moving for 4 minutes to get some browning. Then stir and cook another 3 to 4 minutes until just cooked through. Transfer to a plate (don’t wipe out the pan).
Lower the heat slightly. Add garlic, ginger, and white and light sliced scallions. Cook until fragrant and just golden at the edges, about 30 to 45 seconds.
Return the green beans and chicken to the pan. Whisk the sauce again (cornstarch settles), then pour it in. Cook, tossing, until the sauce thickens and coats everything for1 to 2 minutes.
Spoon over rice and garnish with sesame seeds and dark green parts of the scallions.