3 tablespoons olive oil
1 cup finely chopped yellow onion
2 ribs celery, chopped
2-3 garlic cloves, finely chopped
1/2 teaspoon dried thyme
1/2 cup white wine
1-2 teaspoons chipotle powder
1 quart vegetable or poultry broth
1 1/2 pounds garnet sweet potatoes, peeled and cut into 1 inch chunks
1/2 pound carrots, peeled and cut into 1 inch lengths
1/2 cup whole milk
Salt & pepper to taste
In a large, heavy soup pot over medium heat, warm the olive oil. Add onion, celery, garlic and thyme and cook, stirring, until soft, about 10 minutes. Add wine and chipotle powder and cook until the wine is reduced and alcohol smell dissipates. Add broth, sweet potatoes, carrots and a little salt and pepper. Bring to a boil and simmer until the vegetables are soft, about 25 minutes.
Cool the soup, transfer to a blender and purée until smooth. Return the soup to the pot, add milk and heat through. Season to taste with salt and pepper.
Garnish with plain yogurt and cilantro.