Preheat the oven to 375°F.
For the pastry, combine the flour with salt in a large bowl.
Add in the butter and vegetable fats.
Pour in the chilled water and whisk it until well blended.
Mix it to form soft dough. And then wrap the dough with a plastic wrap and chill for at least 30 minutes.
For the filling, toss with some sugar in a bowl of quartered pear.
Heat the butter with the remaining sugar over medium heat and add in the pear.
Cook it uncovered about 20 minutes until the fruit has been completely caramelized.
Let the pear cool over the pan, at the same time, roll the chilled dough to the size larger than the pan.
Place the pastry on top of pear pie filling and carefully tuck the pastry around the edges.
Place into the preheated oven and bake it for 25 minutes.
Remove it from the oven and let it cool a while.
Run a knife around the pan edge to unmold, invert a palte over the pan and quickly turn the two over together.
Serve it with vanilla ice cream or whipped cream. Slice to serve.