Ingredients
900g/2lb trimmed leeks, thickly sliced
salt and freshly ground black pepper
25g/1oz salted butter
150ml/¼pt crème fraiche
freshly grated nutmeg

Method
1. Cook the leeks in a pan of boiling salted water for 7-10 minutes until just tender. Drain and plunge immediately into icy cold water.
2. After 15 minutes, drain again and dry well with several layers of kitchen paper. Put the leeks into a food processor and pulse until roughly chopped. Remove half, then pulse the remainder until smooth.
3. Heat the butter in a frying pan, add all the leeks and stir over a high heat. Add the crème fraiche and season; stir until hot and bubbling. Serve sprinkled with fresh grated nutmeg.