1. Using a mandolin, a fine slicing disc in a food processor or a very sharp knife, cut the potatoes into wafer-thin slices. Cook in a large pot of lightly salted boiling water for 1–2 minutes until just tender, then drain. Preheat the oven to 425°F (220°C).

2. Heat the oil in a pan and lightly fry the onions with the pancetta for 2–3 minutes until softened, then add the mushrooms and cook for a further 2 minutes. Add the potatoes and rosemary, season with freshly ground black pepper and gently toss, without breaking up the slices.

3. Place the pizza crusts on two lightly greased baking trays, then spread the potato mixture evenly over the tops. Trickle the milk over the topping of both pizzas. Bake for 15 minutes until the potatoes are tender and golden.

4. Remove the pizzas from the oven, cut them into quarters and place two quarters on each plate. Equally divide the chicken among the pieces of pizza, then scatter the arugula and Parmesan shavings over the top. Serve at once.

Variations: For a vegetarian version, omit the chicken and pancetta and top the cooked pizzas with arugula, sliced, hard-boiled egg and thin slices of sun-dried tomato.Drizzle each pizza with 2 teaspoons of the oil from the sun-dried tomatoes. Grate an Italian-style hard cheese suitable for vegetarians (see page 9) over the tops.

Flaked drained canned salmon is good with watercress instead of chicken and arugula. Drizzle the can juices from the salmon over the pizzas.

Serves 4

Preparation time 30 minutes

Cooking time 25 minutes

Each serving

717 calories, 23.5 g fat (5.5 g saturated), 39 g protein, 83 g carbohydrate, 9.5 g fibre