serves 6

ingredients                                         100g/4oz Gruy?re cheese, finely 2 tablespoons olive oil                               grated

800g/1lb 12oz leeks, trimmed and      salt and freshly ground

cut into 1cm/1⁄2in slices                          black pepper

150ml/5fl oz dry sherry

200ml/7fl oz chicken stock                   For the topping

400ml/14fl oz cr?me fra?che               200g/7oz ciabatta breadcrumbs

2 tablespoons wholegrain mustard        3 tablespoons olive oil

3 tablespoons chopped fresh sage        75g/3oz Parma ham, roughly torn 1 tablespoon chopped fresh                  2 tablespoons chopped fresh

flat-leaf parsley                                      flat-leaf parsley

700g/11⁄2lb skinless chicken breast fillets, cut into 1cm/1⁄2in strips

• Heat the oil in a large non-stick frying pan, add the leeks and cook over a gentle heat for 15–20 minutes until softened. Remove with a slotted spoon and put to one side. Add the sherry and stock, bring to the boil and bubble until reduced by about a quarter. Allow to cool.

• Preheat the oven to 190°C/375°F/Gas mark 5.

• In a bowl, mix the crиme fraоche, flour, mustard, sage and parsley together with some salt and pepper,. Mix in the reduced stock and leeks.

• Put the chicken into a 2.3 litre/4pt ovenproof dish, and pour the sauce mixture over. Sprinkle the cheese on top.

• To make the topping, put the breadcrumbs in a bowl with the oil, ham and parsley. Toss together and sprinkle over the chicken.

• Cook the chicken in the oven for 50–60 minutes or until bubbling at the sides. Serve hot