Meanwhile, in a small bowl, whisk together the broth and soy sauce or tamari. Set aside.
In a large skillet over medium-high heat, heat the oil and swirl the pan to coat. Cook the chicken, stirring, for 3 to 4 minutes, or until it browns and is partially cooked. Add the garlic and ginger and cook, stirring constantly, for 15 seconds. Add the broccoli, peas, and carrots and cook, stirring constantly, for 3 to 4 minutes, or until tender-crisp. Add the spinach, sprouts, scallions, and reserved broth mixture. Cook, stirring constantly, for 3 to 4 minutes, or until the spinach wilts and the chicken is no longer pink and the juices run clear.
Fluff the rice with a fork and divide among 4 plates. Spoon the chicken mixture over the rice and serve.