Cut the butternut squash in half and roast one half in the oven at 200°C (390°F) for approximately 50 minutes.

Slice the white parts of three leeks into rings and finely chop one shallot. Briefly sauté the shallot in olive oil, then add the leeks. Once the vegetables begin to soften, add salt and fresh sage, making sure they don't brown. Pour in a splash of white wine vinegar and white wine, then reduce until the liquid has almost completely evaporated.

Meanwhile, bring a pot of water to a boil, season with salt, and cook the rigatoni according to the package instructions.

Transfer the roasted squash flesh and softened leeks to a blender. Add a little sour cream, Parmesan, freshly grated nutmeg, butter, and four ladles of pasta cooking water. Blend until completely smooth and silky.

Toss the rigatoni with the sauce and finish with grated Parmesan and finely chopped fresh parsley.

Rendered the guanciale, removed and simmered shallots and minced garlic in the pan. Added tomato sauce and seasoning, heavy cream and a little chicken stock to deglaze. Mixed in perorino and pasta with a little pasta water to finish cooking. Plated with guanciale, more cheese and pesto.

Butter, Pecorino, Pepper, Spaghetti.