Leek, 1, white part only, halved, rinsed, and thinly sliced
Russet potatoes, 3 large, peeled and cubed
Chicken broth or stock, 2cups (16fl oz/500ml), homemade or purchased
Milk, 3cups (24fl oz/750ml)
Salt and freshly ground pepper
Sharp Cheddar cheese, ½cup (2oz/60g) shredded
Cook the bacon and vegetables
In a large saucepan over medium heat, cook the bacon until crisp, about 5 minutes. Using a slotted spoon, transfer the bacon to paper towels to drain. Pour off all but 2tablespoons of the bacon drippings from the pan and return to medium heat. Add the leek and sauté until translucent, about 2 minutes. Add the potatoes and broth and stir. Bring to a boil, then reduce the heat to low. Cook, covered, until the potatoes are tender, about 15 minutes.
Purée the soup
Raise the heat to medium, add the milk and ½teaspoon pepper, and bring just to a simmer. Using a food processor or blender, process the soup to a smooth purée. Return to the saucepan and reheat to serving temperature. Add the cheese and stir until melted. Season to taste with salt and pepper. Ladle the soup into bowls, sprinkle with the bacon, and serve.