Use a 23cm pie plate. Sift the flours and icing sugar into a bowl. Add butter and rub in with fingertips until mixture resembles fine breadcrumbs. Add water and mix to form a ball, adding extra water, if necessary. Knead gently on floured work surface until smooth; cover in cling wrap and refrigerate for 30 minutes.
Preheat oven to 180 degrees C. Roll dough onto a lightly floured work surface until large enough to line pie plate. Line plate and trim edge. Use scraps of pastry to make a double edge for the rim. Trim and pinch the rim.
Place pie plate on baking tray. Line pastry case with baking paper; fill with dried beans or rice. Bake for 10 minutes. Remove paper and beans; bake for a further 10 minutes or until pastry is lightly browned; cool.
To make the filling, beat eggs, sugar and maple syrup in a small bowl with electric beaters until thick. Stir in the pumpkin, cream and spices.
Pour filling into pastry case; bake in moderate oven for about 50 minutes or until filling is set; cool. Lightly dust with extra sifted icing sugar, if desired.