Step 1 Cook bacon strips to crispy and set aside. Prep the Vegetables: Thoroughly wash the leeks to remove any grit. Slice them thinly and set aside. (*see notes in post for more detailed instructions for cleaning leeks.) Peel and dice the potatoes, and chop the cauliflower into bite-sized florets.
Step 2 Sauté the Leeks: Heat butter in a large pot or Dutch oven over medium heat. Add the sliced leeks and cook for 5-7 minutes, stirring occasionally, until softened and fragrant.
Step 3 Simmer the Soup: Add the potatoes, cauliflower florets, and stock to the pot. Bring to a boil, then reduce the heat to low and let simmer for 20-25 minutes, or until the vegetables are tender.
Step 4 Blend to Perfection: Use an immersion blender to puree the soup to a smooth texture directly in the pot. For a chunkier soup, blend only part of the soup. If using a traditional blender, work in small batches to avoid spills. Always allow steam to escape while blending hot liquids.
Step 5 Finish and Serve: Stir in the cheese after blending the soup but before adding cream. This ensures the cheese melts smoothly into the hot soup without clumping. Stir in cream for added richness, if desired. Season with salt and pepper to taste for your family. This soup is delicious with lots of fresh cracked black pepper. Ladle into bowls and garnish with chives or sliced scallions (green onions), more bacon crumbles, shredded cheese and/or a dollop of sour cream.