Ingredients:
- 2 lbs (900g) Butternut Squash, peeled & cubed
- 2 Tbsp Olive Oil
- Salt & Black Pepper, to taste
- 2 large Leeks, white & light green parts only, thinly sliced
- 3 cloves Garlic, minced
- 1 cup (240 ml) Vegetable or Chicken Stock
- 12 oz (340g) Spaghetti
- 4 Tbsp Unsalted Butter, cold and cubed
- 1 cup (100g) Parmesan Cheese, finely grated, plus extra for serving
- Pinch of Fresh Nutmeg, grated
- 2 Tbsp Fresh Parsley, chopped (for garnish)
Instructions:
- Toss cubed squash with olive oil, salt, and pepper. Roast at 400°F (200°C) for approximately 30 minutes until fork-tender and lightly caramelized.
- While squash roasts, melt 1 Tbsp of butter in a large saucepan or Dutch oven over medium-low heat. Add sliced leeks and sauté gently until softened and translucent (about 8-10 minutes). Add garlic for the last minute of cooking.
- Transfer the roasted squash, sautéed leeks/garlic, and stock to a blender. Blend until perfectly smooth. Taste the base and adjust salt and pepper as needed.
- Bring a large pot of salted water to a rolling boil. Add spaghetti and cook according to package directions, subtracting 2 minutes from the recommended time (it will finish cooking in the sauce). Crucially: Reserve at least 1.5 cups of the starchy pasta water before draining the pasta.
- Return the blended squash mixture to the saucepan over low heat. Add the remaining 3 Tbsp cold butter, stirring constantly until melted and incorporated.
- Add the slightly undercooked pasta directly to the sauce pan. Begin adding the reserved pasta water, starting with 1/2 cup, tossing vigorously to loosen the sauce.
- Remove the pan from the heat completely. Gradually stir in the grated Parmesan cheese, tossing continuously until a velvety, creamy emulsion is achieved. If the sauce appears too thick, add another small splash of pasta water.
- Stir in a grating of fresh nutmeg. Divide the Spaghetti with Butternut Squash Leek Parmesan Sauce among bowls, garnish generously with fresh parsley and extra Parmesan cheese, and serve immediately.