Spicy Miso Butternut Squash Pasta – Brooklyn Delhi

Ingredients

• 2 tablespoons unsalted butter, at room temperature
• 2 teaspoons white miso
• 2-3 teaspoons Roasted Garlic Achaar
• 2.5 pounds butternut squash, peeled and cut into 1/2-inch cubes
• 1 tablespoon olive oil, plus more as needed
• 1 teaspoon kosher salt
• black pepper
• 1 pound mezze rigatoni or other short pasta
• 1/2 cup grated Parmesan, plus more for serving
• 1 cup reserved pasta water
• 2 teaspoons lime zest
• 2 tablespoons lime juice
• 1/4 teaspoon red-pepper flakes (optional)