Preheat oven to 350°F (175°C). Combine cornmeal, flour, butter, and salt in a mixing bowl. Press into pie dish and bake for 15-20 minutes until golden. Cool on wire rack.

In a saucepan, combine sugar and water. Cook until deep amber color, about 10 minutes. Whisk in heavy cream and salt. Cool slightly before layering.

Melt white chocolate in a double boiler. Stir in pumpkin puree, heavy cream, and salt until smooth. Remove from heat.

Pour cooled salted caramel over the crust. Layer pumpkin ganache on top, smoothing surface to remove air bubbles.

Cover loosely with plastic wrap and refrigerate for at least 4 hours or overnight to set.

Make streusel topping by mixing butter, flour, and nuts until crumbly. Bake at 350°F (175°C) for 10-12 minutes. Let cool slightly before adding to pie.

Slice and serve chilled or at room temperature with whipped cream.