- 2 tablespoons olive oil
- 1 medium onion, chopped
- kosher salt and black pepper
- 2 pounds medium sweet potatoes (about 3), peeled and cut into 3/4-inch pieces
- 3 apples (such as Granny Smith or Pink Lady), 1 peeled and chopped and 2 thinly sliced
- 2 cups low-sodium vegetable broth
- pinch ground nutmeg
- 1 cup blue cheese, such as Gorgonzola or Stilton (4 ounces )
- 1/3 cup walnuts
- 16 crackers or crostini
- Heat the oil in a large pot over medium heat. Add the onion, ½ teaspoon salt, and ¼ teaspoon pepper and cook, stirring occasionally, until tender, 6 to 8 minutes.
- Add the sweet potatoes, chopped apple, broth, nutmeg, and 1½ cups water. Bring to simmer and cook, covered, until the potatoes are tender, 12 to 15 minutes.
- Working in batches, transfer the mixture to a blender and puree until smooth, adding more water if necessary to reach the desired consistency. (Alternatively, use a handheld immersion blender in the pot.)
- Serve the soup with the blue cheese, walnuts, crackers, and sliced apples.