- STEP 1
Melt the butter in a large saucepan over a low heat. Add the celery, potatoes and leeks and cook gently for 5 minutes.
- STEP 2
Pour the stock into the pan and add the bay leaf. Bring to the boil, then reduce the heat, cover and simmer for 20 minutes or until all the vegetables are tender. Remove the bay leaf.
- STEP 3
Cool slightly. Using a draining spoon, lift out the vegetables and put them into a blender or food processor with some of the liquid. Whizz to a purÃÂ©e.
- STEP 4
Return the purÃÂ©e to the pan with the rest of the liquid, add the milk and heat gently. Season to taste with salt and pepper.
- STEP 5
Ladle the soup into warm bowls and grind a little more pepper over the top. Scatter over the chopped celery leaves to garnish.