With a combination of puréed vegetables mixed with heavy cream, this soup is impossibly creamy.
Ingredients
2 medium leeks (white and light green parts)
1 medium yellow onion
4 cloves garlic
2 tablespoons unsalted butter
2 tablespoons olive oil
2 sprigs fresh rosemary or thyme
3 pounds mix of root vegetables, such as carrots, parsnips, sweet potatoes, Yukon gold potatoes, or celery root
1/2 cup dry white wine (optional)
6 cups low-sodium chicken broth, water, or combination
1 tablespoon kosher salt, plus more as needed
1/2 teaspoon freshly ground black pepper
1 cup heavy cream
Croutons, for serving
Instructions
Cut 2 medium leeks in half lengthwise and run them under water, allowing water to pass through each layer and wash away any sand. Shake dry and coarsely chop the white and light green parts (discard the rest). Coarsely chop 1 medium yellow onion and 4 garlic cloves.
Heat 2 tablespoons unsalted butter and 2 tablespoons olive oil in a large Dutch oven over medium-high heat. Add the leeks, onions, garlic and 2 sprigs fresh rosemary or thyme. Stir to combine and cook, stirring occasionally, until soft and starting to brown at the edges, about 10 minutes. Meanwhile, peel and coarsely chop 3 pounds root vegetables.
Add 1/2 cup dry white wine, if using, to the Dutch oven. Scrape any bits that have stuck to the bottom of the pan with a wooden spoon. Add the root vegetables, 1 tablespoon kosher salt, and 1/2 teaspoon black pepper. Add 6 cups chicken broth, water, or a combination, and stir to combine.
Bring to a simmer. Cover and simmer until the vegetables are very soft, about 30 minutes.
Remove from the heat. Remove and discard rosemary or thyme sprigs. Add 1 cup heavy cream. Use an immersion blender to blend the soup until very smooth. Alternatively, blend soup in batches in a blender. Taste and season with more kosher salt as needed. If the soup is too thick, thin out with water.
Ladle into soup bowls and top with croutons and a little extra black pepper.
