Silky Potato and Leek Soup with Chives and Crispy Leeks

Bake. Heat butter in a big saucepan or Dutch oven over a mid-sized flame till melted. Add leeks, reduce heat to low, and cook, mixing often, till very soft yet not browned, 10 to 15 minutes. Tip in stock, potatoes, and bay leaf, and season gently with salt and pepper. Bring to the boil over a high flame, reduce to a gentle simmer, cover, and heat till potatoes are fall-apart tender, around 15 minutes. Using a Ricer (Recommended): Take out potatoes off soup using tongs plus move to a bowl. Keep to one side. Discard bay leaf. Move leftover soup in order to a blender. Slowly increase blender speed to high plus blend till completely smooth, around 2 minutes. Return soup in order to a clean pot. Push potatoes through one potato ricer or food mill in the pot using the soup. Beat in buttermilk and heavy cream. Beating often, bring soup to a simmer over a medium-high flame. Beat in grated nutmeg. Taste and add salt if it needs it using salt and pepper and serve with chives or spring onions. Using a Blender (Faster): Tip in heavy cream plus buttermilk to pot. Discard bay leaf. Working a batch after another if you need to, move soup in order to a blender. Slowly increase blender speed to high plus blend till completely smooth, around 2 minutes. Return soup in order to a clean pot, pressing it through a fine sieve using the bottom of one ladle if a smoother texture is wanted. Beating often, bring soup to a simmer over a medium-high flame. Alternatively, chill completely and eat cold. Beat in grated nutmeg. Taste and add salt if it needs it using salt and pepper and serve with chives or spring onions.