Felicity Cloake's perfect leek and potato soup recipe

Perfect leek and potato soup Serves four. 3 fat leeks 40g butter 3 medium floury potatoes 700ml chicken or vegetable stock 1 small bunch chives, chopped, to serve Single cream, to serve Chop off and discard the coarse green tops from the leeks and thinly slice the rest. Rinse well under running water (grit often lurks between the layers) and drain thoroughly. Melt the butter in a large, heavy-based pan over a low heat and add the sliced leeks. Season, cover and leave to sweat for 15 minutes, stirring occasionally to prevent them sticking. Scrub the potatoes and cut into chunks – you need to peel them only if the skins are particularly blemished. Add the potatoes to the leeks and cook for five minutes. Cover the vegetables with stock and bring to a simmer. Partially cover the pan and leave to simmer gently for 45 minutes, until the potatoes are cooked. Puree the soup in a liquidiser or with a hand blender, pour back into the pan, taste and adjust the seasoning as necessary. Reheat and serve with a pinch of chopped chives and a swirl of cream. • Perfect, by Felicity Cloake, is published by Penguin at £18.99. To order a copy for £12.99, go to theguardian.com/bookshop , or call 0330 333 6846.