Cook the spaghetti in boiling salted water according to the package directions to al dente. Drain, and set aside.
While the spaghetti cooks, use the edges of a spoon to peel the ginger. Mince the ginger.
Whisk together the chicken broth, soy sauce, hoisin, sesame oil, and cornstarch in a liquid measuring cup or small bowl. Set aside.
Heat the vegetable oil in a large skillet over medium-high heat until hot. Add the chicken pieces and cook 4 to 5 minutes, turning once, until browned on both sides. Remove the chicken from the skillet, reserving the drippings in the skillet.
Add the ginger and garlic to the drippings, and sauté for 30 seconds or until fragrant. (Keep a watchful eye on the skillet--the ginger and garlic burn easily.) Add the vegetables and 2 tablespoons water. Cover the skillet with a lid and allow the vegetables to steam for 3 minutes or until almost tender. Uncover and cook 1 more minute or until the liquid evaporates.
Return the chicken to the skillet and pour in the chicken broth mixture. Reduce the heat, and simmer for 2 minutes or until the sauce thickens.
Add the spaghetti, and toss gently to coat. Divide the lo mein evenly between serving bowls or plates and serve immediately.