Chicken cordon bleu with pommes parmentier and leeks vinaigrette

Preheat the oven to 170°C/gas 3.

First prepare the pommes Parmentier. Heat the butter and olive oil in a heavy-based frying pan. Add the cubed potato and fry until nut-brown, stirring now and then.

Meanwhile, slice lengthways down the chicken breast and open it out into a butterfly shape. Place between two layers of cling film and beat to flatten out, using a cook's mallet or a rolling pin.

Blend together the Gorgonzola, double cream, garlic, basil, butter and the seasoning.

Spread the Gorgonzola mixture over one half of the chicken breast. Fold the chicken over the filling and push back into shape. Season the chicken with salt and freshly ground pepper.

Coat the chicken breast in flour, beaten egg and then breadcrumbs.

Heat the oil for deep-frying until hot in a wok or deep fat-fryer. Deep-fry the coated chicken breast for 10 minutes. Remove with a slotted spoon to a baking sheet. Bake the chicken in the oven for 10 minutes.

Meanwhile, add the garlic, onion and rosemary to the frying potatoes, mixing well. Season with salt and freshly ground pepper.

. Transfer the potatoes to an ovenproof dish and bake alongside the chicken for 10 minutes.

. Meanwhile, poach the leeks in a saucepan containing water plus half a tablespoon of white wine vinegar and salt for 12-15 minutes, until tender.

. While the leeks are simmering whisk together the remaining vinegar and olive oil to form a vinaigrette. Season with salt and freshly ground pepper. Drain the leeks and toss while hot with the vinaigrette.

. Toss the potatoes Parmentier with the breadcrumbs and lemon juice. Season with salt and freshly ground pepper.

. Serve the chicken cordon bleu and the potatoes with the leeks vinaigrette.