Preheat the oven to 425°F.
Place the squash, onions, and carrot in a large bowl (or Ziploc bag) and toss with the olive oil to coat. Arrange on a baking sheet and season with salt and pepper. Scatter 4 thyme sprigs on top of the vegetables. Roast for 30 minutes or until tender. Discard the thyme sprigs.
Dump the squash mixture, garlic, and spices into a pot and cook over medium high heat for a 2 minutes, stirring to combine. Add the vegetable stock and remaining thyme springs and bring the mixture to a boil. Reduce to a simmer and cook, covered for 10 minutes or until tender. Remove from the heat and let cool slightly. Discard the thyme sprigs.
Working in batches, blend the mixture in a blender until smooth. Feel free to thin with additional broth if it appears too thick. Pour back into a clean pot to keep warm on the stove. Season with salt and pepper to taste.
For the pears, heat the olive oil over medium-high heat in a large sauté pan. Add the pears and cook for about 2 minutes. Add the spices and continue cooking, stirring constantly for another 3 minutes or until the pears are tender and coated with the spices. Set aside.
• Add a big spoonful of spiced pears to each bowl of soup and have your guests stir them into the soup.
• For a smoother, more complex soup, blend the pears into the soup (using the blender, working in batches). This is what I did and end result was outstanding! The spiced pears blended beautifully with the earthy flavors of the roasted butternut squash soup.
• Garnish each bowl with a dollop of crême fraiche or yogurt and, using a toothpick or wooden skewer, sketch little white patterns into the surface of the soup. (Mine turned out kind of ugly, but it’s fun to try!)
• This soup can be made several days in advance–just store in an airtight container in the refrigerator and reheat over medium heat on the stove.