Preheat oven to 350 F. Arrange hazelnuts on baking sheet and toast for 5 minutes. Once cooled, finely chop hazelnuts and drizzle with olive oil.

In cast iron pot, heat 2 tablespoons olive oil. Add shallots and cook until golden brown and soft, around 8 minutes. Add garlic and red pepper and cook until fragrant and garlic is soft.

Stir in squash. Add stock and bring mixture to boil. Reduce heat to simmer and cook until squash is tender, around 10 minutes.

In another pot, bring salted water to boil. Add pasta and cook until al dente. Drain pasta and rinse with cold water.

Once cooled, transfer squash mixture into blender and add 2 cups of Parmesan. Puree until smooth.

Pour 1 cup squash puree onto 13x9 baking dish and spread all across. Add a layer of pasta then pour remaining sauce on top.

Top with another 1/2 cup Parmesan, cover with foil and bake 15 minutes. Uncover and raise temperature to 425 degrees F and continue baking until the top has dark spots around, 12 minutes.

Add basil, hazelnuts, salt and olive oil. Stir to combine and layer with more parmesan and pepper.