Instructions

1. Cut 6 tablespoons unsalted butter into small pieces and let sit at room temperature until softened.
2. Roll out 1 pie dough on a lightly floured work surface into a 12-inch round. Transfer to a regular 9-inch pie pan (not deep dish). Press the dough into the bottom and up the sides. Trim all but 1 inch of the overhanging dough, then crimp the edges. Refrigerate for at least 30 minutes until very cold and firm. Meanwhile, make the streusel.
3. Place 1 cup all-purpose flour, 2 tablespoons packed light brown sugar, 2 tablespoons granulated sugar, and 1/4 teaspoon kosher salt in a medium bowl and whisk to combine. Scatter the butter over the flour mixture. Using your fingers, rub the butter together with the dry ingredients until all of the butter is thoroughly broken down and the mixture feels like damp sand.
4. Cover and refrigerate for at least 15 minutes. Meanwhile, arrange a rack in the lower-middle of the oven and heat the oven to 400°F.
5. Juice 1 medium orange until you have 3 tablespoons. Place 1 1/4 cups granulated sugar, 1/4 cup cornstarch, and 1/4 teaspoon kosher salt in a large bowl and whisk to combine. Add the orange juice, 6 cups fresh or frozen raspberries, and 1 1/2 teaspoons vanilla extract. Gently fold together with a flexible spatula until the sugar and cornstarch are mostly dissolved and the filling is well combined.
6. Line a baking sheet with parchment paper. Place the crust on the baking sheet. Pour the filling into the crust and spread into an even layer. Sprinkle the streusel evenly over the top, going all the way to the edges of the crust.
7. Bake until the filling is bubbling around the edges and the streusel and crust are golden brown, about 1 hour to 1 hour and 15 minutes; check after 50 minutes and tent loosely with aluminum foil if the top is becoming too dark. Transfer the pie to a wire rack and let cool for at least 3 hours before slicing. Serve with whipped cream or vanilla ice cream if desired.