A simpler take on a classic vichyssoise, this is my favorite soup to make in the winter. With a mere three ingredients, it's cheap and quick. The soup manages to taste both sophisticated and comforting all at once. The starch from the potatoes makes it taste cream-laden, despite having no dairy in it. Serve it alongside flaky buttermilk biscuits for a perfect cold-weather meal. —Posie (Harwood) Brien
Clean the leeks carefully, then slice them into thin half-moons. Scrub and dice the potatoes into small cubes.
In a large pot or Dutch oven, heat the oil over medium-high heat. Add the sliced leeks and season with salt and pepper. Cook for about 5 minutes, stirring occasionally, until the leeks soften.
Add the potatoes and the water. Reduce the heat to medium-low, cover, and cook for 15-30 minutes: The soup is ready when the potatoes can be easily poked with a fork. The timing will vary depending on the type of potatoes you use.
Using an immersion blender, puree the soup until smooth. (If you don't have one, transfer the soup to a blender and blend until smooth. Be very careful with the hot liquid!) Taste the soup and season with more salt if needed.