In a large stockpot over high heat add chicken broth, garlic, scallions, ginger, sugar, soy sauce, fish sauce, Tabasco, sesame oil, carrots and if you have it a chicken carcass, wings, skin legs…whatever you have.
Bring your stock to a boil, and then reduce heat to medium-low. Allow the flavors to develop by simmering for 20 minutes.
Remove stock from heat, allow it to sit for20 minutes, then strain the stock into a large bowl, pressing on your solids to get every bit of flavor you can. If you are adding sliced mushrooms, add them now to the broth. Just before you are ready to serve the soup, place your noodles in a large bowl, cover with hot water AND Soak for 5 minutes.
Drain noodles and set them aside. Return your strained broth to your pot and bring to a simmer and add in your shredded chicken, cook for 5 minutes. Add in the lime juice and turn off the heat.
Fill your bowl(s) with the amount of noodles you would like (I like the bowl ¾ full of noodles) then ladle in the soup. Top each bowl with cilantro leaves and serve.