This is a comforting, soul-warming soup you can serve as a chowder or turn into a silky purée.

Ingreadients:

• 2 tablespoons unsalted butter
• 1 tablespoon olive oil
• 4 large leeks (about 8 cups), white and light green parts only, halved lengthwise, halves cut into 1/2-inch-thick half-moons
• 4 large celery stalks (about 2 cups), chopped, plus small, tender leaves for garnish
• 6 large Yukon Gold potatoes (about 9 cups), peeled, quartered lengthwise, and cut into 1/2-inch pieces
• 7 cups water
• 2 tablespoons plus 1 teaspoon jarred chicken stock base (such as Better Than Bouillon)
• 1 cup whole milk
• 1/4 cup heavy cream
• 1 1/2 teaspoons kosher salt
• 1/2 teaspoon black pepper
• Dash of freshly grated nutmeg
• Finely chopped fresh chives and crushed potato chips, for garnish

Direction

1. Melt butter with olive oil in a large, heavy-bottomed saucepan over medium. Add leeks; cook, stirring often, until softened, 5 to 8 minutes. Add celery; cook, stirring often, until tender and deeply saturated in color, about 8 minutes. Add potatoes; stir to coat potatoes in butter and oil. Reduce heat to low, and cook, stirring often, until potatoes are coated in a shiny, milky starch, about 5 minutes. Stir in 7 cups water and chicken stock base; bring to a boil over high. Reduce heat to medium, and simmer, stirring occasionally, until potatoes are just tender and vegetables are softened, about 15 minutes. Remove from heat. Using a ladle, remove 2 cups of cooking stock (liquid only), and reserve in a small bowl. Let remaining soup stand at room temperature 30 minutes.
2. Stir milk, cream, salt, pepper, and nutmeg into soup. Stir in reserved stock, a little at a time, to reach desired consistency. (If desired, use a potato masher to mash some of the soup. To serve pureed, pour soup and reserved 2 cups stock, in two batches, into a blender. Process until smooth, about 20 seconds per batch.) Divide soup evenly among 8 bowls, and garnish with celery leaves, chives, and crushed potato chips.