Vichyssoise

• 2 lb (900 g) leeks
• 1 medium-sized onion
• 1

Trim the tops and roots from the leeks, leaving only the white part. Cut in half lengthways and wash well, then finely chop the leeks. Peel and finely chop the onion. Melt the butter in a large saucepan over low heat, add the leeks and onion, cover with a pan lid, and cook gently for 5 minutes until softened and translucent. Meanwhile, peel and cut the potatoes in evensized chunks.

Stir