Heat oil in large pot over medium heat.Sauté garlic, ginger, green onions, shredded carrot, and mushrooms. Cook for 3 minutes.Add broth, coconut milk, and fish sauce.Bring to a gentle boil, and reduce heat to a simmer.Add chicken and simmer for 7-10 minutes.Stir in lime juice and cilantro.Serve over prepared zucchini noodles.