Peel and dice butternut squash. Toss with 1 tbsp olive oil and salt. Roast on a sheet pan for 30-40 minutes, until tender.
Bring a pot of salted water to a boil.
While squash is roasting, add 1/4 cup of vegetable oil to a small skillet over medium heat. Once shimmering, add fresh sage leaves and fry for 15 seconds. Transfer to paper towel.
When squash is finished, add pasta to salted water and cook according to package directions.
Meanwhile, add squash to a blender with vegetable broth, milk, tomato paste, salt, pepper and remaining 2 tbsp olive oil. Blend until smooth and creamy.
Toss cooked pasta with sauce. Top with fried sage, hazelnuts and parmesan (optional).