Step 1

In a 4- to 5-quart slow cooker, combine the potatoes, leeks, bay leaf, garlic, smoked paprika, and thyme. Add the stock and water. Cover, and cook on low for 8 to 10 hours.

Step 2

Remove and discard the bay leaf. Using an immersion blender, puree the mixture until smooth. (Or, if working in batches, transfer the mixture to a blender. Cover and blend until smooth. Return the pureed mixture to the slow cooker.) Season with salt and pepper and, if needed, thin with additional water. Serve garnished with snipped fresh chives.