Chipotle Sweet Potato Soup

1 tablespoon unsalted butter

1 1/2 cups thinly sliced onions

2 tablespoons brown sugar

1 teaspoon salt

1/4 teaspoon ground cinnamon

4 cloves garlic, minced

6 cups (1 inch chunks) sweet potatoes, 3 lbs.

1 chipotle chile in adobo sauce

4 cups fat free low sodium vegetable broth

1 cup half and half

3 tablespoons fresh lime juice

Sour cream for garnish

Chopped fresh chives for garnish

Melt butter in stockpot over medium high heat. Add onions, brown sugar, salt and cinnamon and sauté for 4 minutes or until onions are light brown. Add garlic and sauté for 1 minute. Stir in sweet potatoes and chipotle chile and sauté for 10 minutes. Stir in broth and bring to a boil. Reduce heat to low. Simmer for 25 minutes or until sweet potatoes are tender, stirring occasionally. Remove from heat and cool for 5 minutes. Pour 1/2 of the sweet potato mixture into a blender and process until pureed. Pour puree into a soup tureen and cover to keep warm. Repeat process with the remaining sweet potato mixture. Heat half and half in microwave safe bowl on high for 30 seconds or until hot. Stir the half and half and lime juice into soup and garnish with sour cream and chives. Serves 9