For the pumpkin purée: preheat the oven at 180°C. Wash the pumpkin without removing its peel, chop it into equally sized chunks and put them in a sheet pan covered by parchment paper
Cover with aluminium foil and bake in the oven for about 1 hour: after baking, it must be possible to pierce the pumpkin with a fork.
Take out from the over let it cool down, peel the chunks and put them in a bowl, masking them with a fork to obtain an even purée.
For the dish: preheat the oven at 180°C. Pour the pumpkin purée, the egg, the parmesan, the rounds of frankfurters (saving two rounds for the mummy's eyes), the flour, the nutmeg and a pinch of salt and pepper in a bowl and mix the ingredients.
Cover a springform pan with parchment paper and put shortcrust pastry on it, cutting the excess pastry and putting it aside.
Pierce the bottom of the pastry with the prongs of a fork and pour the filling, folding the edges inwards.
Cut small strips from the excess pastry and decorate the surface of the pie, until it looks like a (mouthless) mummy; brush the beaten egg on the strips.
For the mummy's sewn mouth, put 1 horizontal piece of pastry over 5 vertical ones.
Bake the frankfurter mummy for about 50 minutes, until its surface turns golden brown.
Then, take out from the oven, put the mummy's eyes and let it cool down before serving cut into slices.