8 cups peeled and cubed cushaw squash (about 3/4-inch)
1/2 (14.1-ounce) package refrigerated piecrusts
1/3 cup firmly-packed light brown sugar
2 large eggs
2 tablespoons heavy whipping cream, room temperature
2 tablespoons melted unsalted butter, room temperature
1 1/2 teaspoons vanilla extract
1 teaspoon ground cinnamon
1/4 teaspoon ground nutmeg
1/3 teaspoon ground allspice
1/3 teaspoon salt
Sweetened whipped cream, to serve
Preheat oven to 400°. Place racks in center of oven. Line 2 rimmed baking sheets with foil, and lightly spray with cooking spray.
Divide squash evenly between baking sheets. Cover with foil, and bake 35 to 45 minutes or until tender. Rotate pans half way through cooking time. Let cool to room temperature.
Line a fine mesh sieve with a double layer of cheesecloth, and place over a large bowl. Place contents of 1 sheet pan into prepared sieve. Carefully bring together ends of cheesecloth, and squeeze into a ball shape, ringing out excess water from the squash. Repeat with remaining squash. Combine squash in sieve over a large bowl; cover, and let stand in refrigerator 1 hour or overnight. Roasted squash should yield about 2 cups.
Preheat oven to 375°.
On a lightly floured surface, roll piecrust into a 12-inch circle. Transfer to a 9-inch pie plate, pressing into bottom and up sides of plate. Fold edges under, and crimp as desired. Top with a piece of parchment paper, letting ends extend over edges of plate. Add pie weights. Bake 15 minutes or until golden brown. Carefully remove paper and weights. Let crust cool on a wire rack while preparing filling.
Reduce oven temperature to 350°.
In the work bowl of a food processor, combine squash, brown sugar, eggs, cream, butter, vanilla, cinnamon, nutmeg, allspice, and salt. Process until smooth, and spoon into piecrust. Cover edge of piecrust with foil to prevent excess browning. Bake 40 to 45 minutes or until filling is set. Serve warm or at room temperature. Top with a dollop of whipped cream.