For pie crust- In a large bowl, combine flour, sugar and salt. Add the cold cubed butter and using a pastry cutter or a food processor, cut the butter into the dry ingredients. Stop when pea sized bits of flour coated butter remain- do not over cut into fine crumbs. If using a food processor, use the pulse setting until this texture is achieved.
Add the iced water 2 tablespoons at a time until the dough comes together. Turn dough onto a lightly floured surface and fold the dough onto itself for a few minutes then form it into a ball and cut in half. Flatten each half into a disc, wrap tightly in cling wrap and refrigerate for at least 1 hour.
Once chilled, allow dough to rest on bench for 10 minutes then with a lightly floured rolling pin, roll out one disc for the base of your pie, about 5mm thick. Place pastry base into pie dish. Roll the other disc out to the same thickness and cut 1cm strips of dough. Set aside and make the filling.
For pie filling- To a large bowl, add the chopped pears, lemon juice, sultanas and stir to combine.
In a small bowl, stir together the sugar, cinnamon, nutmeg and arrowroot. Sprinkle this over the pears, then add the walnuts and combine well.
Place the filling into the uncooked pie shell. Add the strips of pastry to the top, crossing them over randomly to mimic the wraps of a mummy. Gently pinch down the strips of pastry to the edge of the pie dish to secure the ends.
Brush the strips of pastry with milk and sprinkle with sugar.
Bake in a pre-heated oven at 180°C (fan forced) for 55 minutes until the crust is golden brown. Allow to cool for 15 minutes and decorate with the candy eyes.