Make the mash: boil the potatoes in
salted water for 15-20 mins until tender.
Drain and mash well. Stir in the milk, then
the Parmesan and basil. Season with
black pepper and keep warm.
Meanwhile, sit the chicken breasts on a
board and cut through them horizontally
leaving one side attached. Open them up
like a book and lay a basil leaf on top of
each, topped with a slice of prosciutto.
Secure with a cocktail stick.
Heat the oil in a large, non-stick frying
pan and add the chicken breasts, hamside
down. Cook for 2-3 mins until golden,
then turn over and cook for 2 mins more.
Pour over the Marsala and allow to
bubble for 1 min. Add the stock and
simmer for 5 mins until the chicken is
cooked. Lift the chicken out, cover to
keep warm, then boil the pan juices to
reduce a little. Serve with the basil mash
and a green salad on the side, if you like.