Roll out two thirds of the pastry on a floured work surface and line the pie dish. Peel, quarter and core the pears, then slice thickly into a bowl. And add the Cranberries.
Mix together the sugar, lemon juice and zest and stir gently into the pears and cranberries. Place the pear and cranberries into the lined pie dish. Dot with butter, and sprinkle with rosemary.
Roll out the pastry and place on top of the fruit. Seal the edges well. Make a small hole in the top to allow steam to escape.
Make decorations from any pastry trimmings (leaves are simple to make) and seal with a little water. Egg wash with lightly beaten egg and sprinkle with the remaining sugar.
Bake at 190C/375F/Gas 5 for 30-40 mins until the fruit is tender and the top is golden brown. Serve with custard.
