Preheat your oven to 325°F. Place pumpkin puree on a parchment-lined baking sheet and roast for 20–30 minutes until thick.

In a heat-safe bowl, combine cooled roasted pumpkin with melted white chocolate, heavy cream, corn syrup, unsalted butter, pumpkin pie spice, and salt. Blend until smooth and refrigerate for 1–2 days.

Combine water, white sugar, and corn syrup in a saucepan over medium heat. Stir until sugar dissolves, then boil undisturbed until golden (~8–10 minutes). Whisk in butter, cream, vanilla, and salt, then cool.

In a mixing bowl, combine flour, cornmeal, powdered sugar, and salt. Cut in butter until crumbly. Add vinegar and water until dough forms. Chill for 30 minutes, roll out, and blind bake for 15–20 minutes at 350°F.

Mix rolled oats, flour, butter, and powdered sugar until crumbly. Bake at 325°F for 15 minutes, stir occasionally, then cool.

Pour cooled salted caramel into the baked crust. Refrigerate for 2 hours until set. Pour chilled ganache over caramel, smooth top, and refrigerate overnight.

Whip fresh cream until soft peaks form. Spread over pie, sprinkle cooled streusel, and slice. Serve cold.