Soup:
3 tablespoons vegetable oil
1 onion, diced
3 cloves garlic, minced
1 teaspoon Mexican oregano
2 large sweet potatoes (about 2 pounds), peeled and cubed
4 chipotle chiles plus 2 tablespoons adobo from 1 can of chipotles en adobo
6 cups chicken or vegetable broth
1 cup heavy cream (or coconut cream to make it vegan)
Salt and pepper
Chopped cilantro, for serving
Crema:
1 tablespoon cumin
1 cup sour cream
Juice of 1 lime
Salt
Toasted corn:
1 cup frozen corn, thawed
In a large saucepan or Dutch oven, heat oil over medium until hot. Add onion and cook until translucent, about 3 minutes. Add garlic and oregano and cook 1 minute. Stir in sweet potatoes, chipotles and adobo. Add broth and simmer over medium until sweet potatoes are soft, about 25 minutes.
Meanwhile, make cumin-lime crema and toasted corn. In a small skillet over low heat, toast cumin until fragrant. Remove from heat and whisk in sour cream and lime juice. Season with salt and let cool while finishing the soup. Heat a medium skillet over medium-high and add corn, spreading into a single layer. Let corn toast until lightly charred, about 5 minutes. Remove from heat. Working in batches, transfer broth mixture to a blender and puree until smooth. Return soup to saucepan and stir in cream. Season to taste with salt and pepper. Serve soup topped with a swirl of crema and a sprinkle of toasted corn and chopped cilantro.