Heat oven to 450°F (230ºC). Toss the squash in ¼ cup olive oil and spread in a single layer on a baking sheet. Roast for 30 minutes, until you can stick a fork in the squash and it slides off cleanly. Let cool.
Heat a large pot over medium heat. Add the remaining 2 tablespoons of olive oil and heat through. Add diced carrot, celery and onion to the pot, stirring occasionally until onion is translucent, about 8 minutes.
Add the roasted squash, thyme and vegetable broth and bring to a boil. Reduce heat to medium-low and simmer for 15 minutes.
Let the soup cool slightly then use a blender to puree the soup in batches. Alternatively, puree the soup using an immersion blender. Stir in the maple syrup.
For the maple cream:
In a small bowl stir together the crème fraîche and maple syrup until thoroughly combined.
For serving:
Serve soup hot in bowls and drizzle a teaspoon of the maple cream over the top of each soup bowl.