Prepare the Crust: In a large bowl, mix together the flour, granulated sugar, and salt. Cut in the cold butter until the mixture resembles coarse crumbs. Add cold water, one tablespoon at a time, until the dough just begins to come together. Form the dough into a disk, wrap it in plastic wrap, and refrigerate for 30 minutes.
Pre-Bake the Crust: Preheat your oven to 350°F (175°C). Roll out the chilled dough on a lightly floured surface to fit a 9×13-inch baking dish. Transfer the dough to the baking dish, pressing it into the bottom. Prick the crust all over with a fork and pre-bake for 10-12 minutes, or until lightly golden. Let it cool slightly.
Make the Pumpkin Filling: In a large bowl, whisk together the pumpkin puree, granulated sugar, brown sugar, cinnamon, nutmeg, cloves, ginger, eggs, and evaporated milk until smooth. Pour the pumpkin mixture over the pre-baked crust.
Prepare the Crisp Topping: In a medium bowl, combine the flour, oats, brown sugar, and cinnamon. Stir in the melted butter until the mixture becomes crumbly.
Assemble and Bake: Evenly sprinkle the crisp topping over the pumpkin filling. Bake in the preheated oven for 40-45 minutes, or until the topping is golden brown and the pumpkin filling is set.
Cool and Serve: Allow the Pumpkin Pie Crisp to cool slightly before serving. Top with whipped cream or a scoop of vanilla ice cream if desired.