Preheat oven to 375°F (190°C). Prepare a 9-inch pie pan with pie crust.

In a medium saucepan, combine cranberries, granulated sugar, brown sugar, cornstarch, and salt. Cook over medium heat 5–7 minutes until cranberries burst.

Remove from heat and stir in orange zest and vanilla extract. Let cool slightly.

In a medium bowl, mix flour, oats, brown sugar, salt, and cinnamon. Cut in cold butter until mixture resembles coarse crumbs.

Pour cranberry filling into pie crust and evenly sprinkle streusel topping over the filling.

Place pie on a baking sheet and bake 35–40 minutes until topping is golden and filling bubbles.

Cool completely for at least 2 hours before slicing.

Optional: dust with powdered sugar or drizzle with glaze before serving.