Carefully run a sharp knife down the length of each stalk of lemongrass and peel back the rough top layer and discard. Chop the stalks into 3-inch chunks.

Add the chicken broth, lemongrass, and grated ginger to a stock pot and bring to a full boil. Cook at a boil for 2 minutes.

Add the remaining ingredients to the pot, and return soup to a boil. Reduce the heat and cook covered for 10 minutes at a rolling but controlled boil, or until the vegetables reach desired done-ness. 

Taste the soup for flavor and add more sea salt, lime juice, and/or sriracha to taste. Before serving the soup, remove and discard the lemongrass stalks!