Coconut Lemongrass White Bean Soup

4 cups chicken or vegetable broth
2 teaspoons minced fresh ginger
1 large lemongrass stalk, ends trimmed, cut into 1-inch pieces, smashed (if the stalk seems dry, peel off the outmost layer before smashing)
grated zest of 1 lime
1 14-oz. can coconut milk
1/4 cup lime juice
3 tablespoons Thai fish sauce
1 teaspoon cane sugar 
1 tablespoon red chili paste
pinch cayenne pepper
2 cups bok choy, thinly sliced
1/2 lb. mushrooms, thinly sliced
2 cans white beans, drained (cannellini, navy, etc.)
Chopped fresh cilantro for garnish

1. In a large saucepan, combine the broth, ginger, lemongrass and lime zest. Place over medium heat and bring to a boil. Reduce heat and simmer for 1 minute.
2. Add the coconut milk, stir to combine and return to a simmer. Add the lime juice, fish sauce, sugar, chili paste, and cayenne; stir well and simmer for 5 minutes.
3. Add the bok choy, mushrooms, and beans. Bring to a simmer and cook for 5 minutes. Taste and adjust seasonings. Serve garnished with fresh cilantro.

Serves 6