In bowl, whisk together chicken broth or water, black bean sauce, cornstarch (or arrowroot flour) and rice vinegar; set aside.
In large wok or skillet, heat 1 tbsp olive oil over high heat; stir-fry chicken, until ready, adding more oil if necessary. Using slotted spoon, transfer to bowl.
Add remaining olive oil, onion, garlic and ginger root to wok. Stir-fry over medium heat until fragrant, about 1 minute.
Add green beans, broccoli, carrots and stock; cover and steam until tender-crisp, 3 to 5 minutes. Return all ingredients to pan. Pour in sauce; cook, stirring, until glossy and thickened, about 4 minutes.
Sprinkle with green onion, and enjoy!