For sauce, in a small bowl stir together broth, balsamic vinegar, and cornstarch; set aside.
Pour oil into a wok or large skillet. (Add more oil as necessary during cooking.) Preheat over medium-high heat. Stir-fry ginger in hot oil for 15 seconds. Add carrots; stir-fry 1 minute. Add broccoli and stir-fry 3 to 4 minutes or until vegetables are crisp-tender. Push vegetables from center of wok.
Stir sauce; add sauce to center of wok. Cook and stir until thickened and bubbly. Stir all ingredients together to coat with sauce. Cook and stir about 1 minute more or until heated through. Sprinkle with nuts. Makes 4 servings.