Preheat the oven to 400°F.

In a large bowl, toss squash with 2 tablespoons of the oil, 1/4 teaspoon of the salt and 1/4 teaspoon of the pepper.

Arrange squash in a single layer on a large baking sheet.

Roast, tossing occasionally, until squash is tender and golden brown, 25 to 30 minutes.

Transfer to a large bowl and set aside.

Meanwhile, heat remaining 1 tablespoon oil in a large skillet over medium-high heat.

Add onion and cook, stirring often, until browned, 7 to 9 minutes.

Add wine and cook, scraping up any brown bits, for 1 minute more.

Add onion to bowl with squash then add Parmigiano Reggiano, hazelnuts, egg, bread crumbs, remaining 1/4 teaspoon salt and remaining 1/4 teaspoon pepper and toss gently to combine.

Transfer mixture to pie crust, pat down lightly and bake until crust is golden brown and filling is hot, about 40 minutes.

Set aside to let cool for 10 minutes before slicing and serving.