Preheat the oven to 425F. Peel and chop the pumpkin or squash and spread out on a rimmed baking sheet. If you like, core and quarter the pears and add them to the sheet too. Drizzle everything with oil and toss with your fingers to coat. Roast for 30 minutes, stirring once or twice, or until soft and golden on the edges.

In a medium saucepan or small pot, heat a drizzle of oil with a blob of butter over medium-high heat and saute the onion for a few minutes, until soft. Add the ginger and cook for another minute. Add the roasted squash and pears (if they're raw, just chop and toss them in, skins and all) and enough stock to cover. Bring to a simmer and cook for 20 minutes, or until everything is very soft. Add a big pinch of salt and puree with a hand-held immersion blender (or transfer in batches to a regular blender) until smooth. Serve hot, sprinkled with crumbled goat cheese.