Silken Turnip and Potato Soup

• FAST
• MAKE-AHEAD

Ingredients

1. 6 tablespoons unsalted butter
2. 4 medium onions, thinly sliced
3. 3 pounds turnips, peeled and thinly sliced
4. 1 1/2 pounds baking potatoes, peeled and thinly sliced
5. Salt
6. 6 cups chicken stock or canned low-sodium broth
7. 1/4 teaspoon freshly grated nutmeg
8. 1/4 cup finely shredded basil, for garnish

1. In a large heavy stockpot or casserole, melt the butter until it foams. When the foam subsides, add the onions and cook over moderate heat until softened but not browned, about 5 minutes. Add the turnips and potatoes and stir to coat with the butter. Add 2 teaspoons of salt, cover and cook over low heat, stirring occasionally, until tender, about 20 minutes.
2. Stir in the chicken stock and bring to a simmer. Cover partially and cook over moderate heat until the vegetables are very tender, about 10 minutes.
3. Working in batches, puree the soup in a blender until perfectly smooth. Return the soup to the pot and season with salt and the nutmeg. Ladle the soup into shallow bowls and garnish with the basil before serving.