Ingredients

• 1/4 cup blanched hazelnuts
• 12 ounces fresh orecchiette or other fresh or dried small pasta
• Kosher salt
• 2 tablespoons olive oil
• 1/2 small butternut squash, peeled, cut into 1/2" pieces (about 2 cups)
• 2 garlic cloves, thinly sliced
• 1/2 teaspoon crushed red pepper flakes, divided
• 1/4 cup (1/2 stick) unsalted butter, cut into pieces
• 1 tablespoon fresh lemon juice
• 1/4 cup grated Parmesan plus more for serving
• 4 tablespoons torn fresh mint leaves, divided
• Freshly ground pepper

Instructions

1. Preheat oven to 350°F. Spread out hazelnuts on a small rimmed baking sheet and toast, tossing occasionally, until golden, about 6 minutes. Let cool, then coarsely chop; set aside.
2. Cook pasta in a large pot of boiling salted water, stirring occasionally, until al dente (about 5 minutes for fresh pasta). Drain, reserving 1 cup pasta cooking liquid.
3. Meanwhile, heat oil in a large skillet over medium-high heat. Add squash and cook, tossing occasionally, until crisp-tender, about 5 minutes. Add garlic and 1/4 teaspoon red pepper flakes and cook, stirring, just until garlic begins to brown, about 2 minutes. Immediately add 1/2 cup pasta cooking liquid to keep garlic from burning; reduce heat to low and gradually add butter, swirling skillet and adding more pasta cooking liquid as needed, until a thick, glossy sauce forms.
4. Add pasta to skillet with squash and sauce and toss to coat. Add lemon juice, 1/4 cup Parmesan, 2 tablespoons mint, and remaining 1/4 teaspoon red pepper flakes and toss to combine; season with salt and pepper.
5. Serve pasta topped with reserved hazelnuts, more Parmesan, and remaining 2 tablespoons mint.
6. DO AHEAD: Hazelnuts can be toasted 5 days ahead. Store airtight at room temperature.