Leek and Potato Soup, the Right Way

Method

1. Prepare the leeks. Cut off the dark green tops and roots. Halve each leek lengthwise, then slice into half-moons. Soak in a bowl of cold water, swishing to release any grit, then lift them out with your hands — the grit stays behind.
2. Cook them slowly. Melt the butter in a heavy pot over medium-low heat. Add the leeks and a pinch of salt. Cook, stirring occasionally, for 12 to 15 minutes — they should soften and turn translucent without browning. This step is where the flavor lives. Do not rush it.
3. Add potatoes and stock. Add the potato chunks and stock. Bring to a simmer and cook, partially covered, for about 20 minutes, until the potatoes are completely tender when pierced with a knife.
4. Blend carefully. Off the heat, use an immersion blender in short pulses until smooth but not glossy — about 20 seconds total. Stir in the milk or cream if using. Taste, season with salt and white pepper.
5. Serve. Ladle into warm bowls. Finish each with a small swirl of cream, a generous pinch of chives, and a single grind of pepper.

A leek and potato soup tells you everything about the cook who made it. There is nowhere to hide.

Notes & substitutions

• Vegetarian Vegetable stock works beautifully. Make it a good one — a homemade or a high-quality boxed brand.
• Make ahead The soup keeps in the refrigerator for three days. The flavor deepens overnight. Thin with a splash of stock or milk when reheating.
• Texture For a perfectly silky texture, pass the soup through a fine-mesh sieve after blending. Optional, but a real upgrade.
• Cold version Chill overnight, thin with buttermilk, garnish with chives and a drizzle of olive oil. That is vichyssoise.