Preheat the oven to 375°F. Peel the butternut squash, cut it in half lengthwise, scoop out the seeds then dice into cubes.

Spread the squash evenly on a large baking sheet then place the cloves of garlic, with the skin on, around the squash. Drizzle with olive oil then sprinkle with salt and pepper. Roast the butternut squash in the preheated oven for 35-40 minutes, or until it's fork-tender.

While it's roasting, boil your pasta according to the package directions in a large pot with salt then rinse and set aside. Additionally, you can fry the sage and walnuts. Melt the butter or vegan butter in a large saucepan over medium-high heat. Once it's melted and shimmering, add the sage and walnuts and stir frequently for 2-3 minutes until the sage crisps and the walnuts toast. Transfer them to a paper towel to drain.

When it's done, carefully transfer the squash to a heat-safe blender with the rest of the sauce ingredients. Blend on high until it's really smooth and creamy.

When it's done, add the cooked pasta and sauce to the pan you used to cook the sage and walnuts. Mix them together and cook on medium heat until warmed all the way through. Top with sage and walnuts before serving.