For the pastry, put the flour in a heap on a work surface, mix with the sugar and salt and make a well in the middle of the flour. Cut the butter into small pieces and scatter around the well. Break the egg into the middle, add the vinegar and approximately 50 ml lukewarm water and chop all the ingredients with a knife until they resemble breadcrumbs.
Quickly combine to a dough using your hands, form into a ball, wrap in plastic wrap and chill for about 30 minutes.
Roughly dice the pumpkin. Melt the butter, add the pumpkin, spices (cinnamon, nutmeg, cloves) and maple syrup and sweat briefly, stirring. Add the milk, cover and cook for about 10 minutes, or until the pumpkin is soft. Mix the pumpkin to a puree with a tablespoon and leave to cool.
Preheat the oven to 200°C (180C fan) 400F, gas 6.
Knead the dough briefly and roll out between 2 sheets of baking parchment to a circle a little bigger than the pie dish. Line the pie dish with the pastry and cut off the excess pastry at the edge. Prick the pastry several times with a fork.
Mix the pumpkin puree with the sugar, cream, cornstarch and egg yolks. Beat the egg whites until stiff and fold into the pumpkin puree. Spread the mixture smoothly in the pastry case and bake for 35-40 minutes.
Take out of the oven and leave to cool. Before serving, mix the cranberries with the sugar. Place in the middle of the pumpkin pie and serve.