Slice the squash in half lengthwise and scoop out the seeds with a large spoon.
Place the squash, cut side down, in a shallow bowl (one that will fit in your microwave).
Add water, cover with plastic wrap and microwave for 8-9 minutes, rotating once, until squash is tender.
Remove from microwave and let cool until you can handle it. Then, carefully peel away the skin of the squash and cut squash into chunks.
Heat the olive oil over medium heat in a large pot, and add the onion, carrot, potatoes, apples or pears, and squash.
Cook 5-7 minutes or until lightly browned.
Pour in enough chicken stock to barely cover vegetables.
Bring to a boil, then reduce heat to low, cover and simmer 40-50 minutes, until vegetables are tender.
Remove from heat and allow to cool slightly.
Transfer the soup to a blender, and blend until smooth.
Return to pot, and stir in any remaining chicken stock until soup is a desired consistency.
Add salt and pepper to taste.
Serve with a dollop of sour cream and top with toasted walnuts and minced chives for your fancy schmancy presentation.