1. Preheat oven to 400oF. In a large bowl, toss together butternut squash, carrots, onion, thyme, salt, pepper and olive oil. Spread in a single layer on a baking tray and roast vegetables for 40-50 minutes, until butternut squash and carrots are tender (when pierced with a fork or knife, it should come out easily). Transfer roasted vegetables to a large saucepan and add vegetable broth, apple cider, cinnamon, ginger and nutmeg. Heat through. Puree soup using an immersion blender, regular blender or food processor.
2. When ready to serve, ladle soup into serving bowls. Top with a dollop of sour cream or crème fraiche and garnish with fresh chives or toasted pumpkin seeds.
3. For a pretty design, make a spiral design of sour cream or crème fraiche on top of soup and use a sharp knife to draw lines from one side to the other as if you’re cutting a pie into sixteen slices.