Make the crust: Whisk together flour and salt. Cut in butter and shortening using a pastry blender or food processor until mixture resembles coarse crumbs. Gradually add ice water, mixing until dough just comes together. Wrap in plastic wrap and chill for at least 30 minutes.

Preheat oven to 375°F (190°C). Roll out dough and fit into a 9-inch pie plate. Trim and crimp edges. Prick bottom with a fork and bake for 15 minutes, or until lightly golden.

Make the caramel: In a medium saucepan, combine butter and sugar over medium heat. Cook, stirring constantly, until sugar is dissolved and mixture is amber in color. Carefully whisk in cream and corn syrup (it will bubble). Stir in salt.

Make the pumpkin custard: In a large bowl, whisk together pumpkin puree, evaporated milk, eggs, cinnamon, ginger, cloves, nutmeg, sugar, and salt until smooth.

Pour caramel into the pre-baked pie crust. Pour pumpkin custard over the caramel.

Bake for 45-50 minutes, or until custard is set and a knife inserted near the center comes out clean. Let cool completely before serving.

Refrigerate for at least 4 hours before serving for best results.