Preheat the oven to 400°F (200°C). Cut the pumpkin in half, scoop out the seeds, and place it cut-side down on a baking sheet. Roast for 30-40 minutes, or until the flesh is tender and easily pierced with a fork. Let it cool slightly, then scoop out the flesh and set it aside. (If using canned pumpkin puree, skip this step.)

1. Cook the pasta according to the package directions. Drain and set aside, reserving 1/2 cup of the pasta cooking water.
2. While the pasta is cooking, heat olive oil in a large skillet over medium heat. Add the sliced mushrooms and cook until they release their moisture and become golden brown, about 8-10 minutes.
3. Add the minced garlic and cook for an additional minute until fragrant.
4. Add the roasted pumpkin flesh (or canned pumpkin puree) to the skillet along with the vegetable broth. Stir until the mixture becomes smooth and well combined.
5. Add the heavy cream (or coconut cream) and ground nutmeg, and stir to create a creamy sauce. Season with salt and pepper to taste. If the sauce is too thick, add a little reserved pasta cooking water to reach your desired consistency.
6. Add the spinach to the skillet and stir until it wilts into the sauce.
7. Toss the cooked pasta into the pumpkin sauce and stir until the pasta is well coated. Add fresh herbs like sage or thyme if using.
8. Serve the pasta warm, topped with freshly grated Parmesan cheese if desired.