LEMONGRASS-GINGER SOUP WITH MUSHROOMS

6 cups chicken stock
6 to 8 oz. oyster mushrooms
3 lemongrass stalks
2 tsp. lime zest
4 nickel-sized slices fresh ginger
1 Persian lime
3 to 4 small hot chiles, optional
1/4 cup fresh cilantro
2 Tbsp. nam pla (fish sauce)

In 3-quart pot over medium heat, heat stock.

While stock is heating, trim 2 stalks of lemongrass of their tough outer layers, bruise them with back of knife, cut in sections and add to stock with ginger and about 1/4 of minced chiles (seeded and minced). Simmer about 15 minutes. You may prepare this in advance, cover and refrigerate for up to 2 days before proceeding.

Peel all hard layers off remaining stalk of lemongrass and mince tender inner core; reserve.

When ready to eat soup, remove lemongrass and ginger. (Reheat if soup was refrigerated.) Add 1 tablespoon nam pla and mushrooms (roughly chopped; shiitakes may be substituted). Taste broth and add more chiles if desired, as well as some salt if necessary.

TO SERVE:
In bottom of four warm bowls, sprinkle some chili, grated lime zest (or minced lime leaves), lime juice, minced cilantro and minced lemongrass. Ladle soup into bowls and add 1 teaspoon of nam pla to each bowl. Serve piping hot.

Makes 4 servings
Adapted from source: The Minimalist Cooks at Home: Recipes That Give You More Flavor from Fewer Ingredients in Less Time by Mark Bittman