In a medium saucepan, precook potatoes and carrots, covered, in enough boiling water to cover about 10 minutes or just until tender. Drain. Set aside.
Cut chicken into thin bite-size strips. Set aside.
For sauce, in a small bowl stir together water, cornstarch, bouillon granules, thyme, salt, and pepper. Set aside.
Pour cooking oil into a wok or large skillet. (Add more oil as necessary during cooking.) Preheat over medium-high heat. Stir-fry onions in hot oil for 2 minutes or until crisp-tender.
Add chicken to the hot wok; stir-fry for 2 to 3 minutes or until no pink remains. Push chicken from the center of the wok.
Stir sauce. Add sauce to the center of the wok. Cook and stir until thickened and bubbly. Add cooked potatoes and carrots. Stir all ingredients together to coat with sauce. Cover and cook for 2 minutes more or until heated through. Stir in parsley. Serve immediately. Makes 4 servings.