Sounds like a strange combination for a soup, but this is delicious. The apples add just enough sweetness to offset the tangy curry.
I borrowed this recipe from Ina Garten, the Barefoot Contessa. Its the most popular soup served in her restaurant and the best of the squash or pumpkin soup recipes I've tried. If you don't like curry, this isn't a recipe for you. I like curry, but cut the amount Ina uses in half (she uses 2 tablespoons, and I use only 1). If you are a real curry lover, you can increase the amount.
2 T olive oil
1 large sweet onion, chopped
1 T mild curry
2 large butternut squash
4 large apples
2 tsp salt
1/2 tsp black pepper
2 cups (more or less) apple cider or apple juice
pint of sour cream (optional)
In a large stockpot, combine the butter, olive oil, onion and curry. Cook over medium heat, uncovered, for 15 to 20 minutes, until the onions are soft. I stirred the mixture frequently to prevent it from sticking, as the curry absorbs the oil and thickens.
While the onion is cooking, peel the squash (I use a potato peeler). Cut in half and scrape out the seeds. Cut the squash in 1 or 2 inch chunks. Peel, core and quarter the apples.
In the stockpot, combine the squash, apples, salt, pepper, and 2 cups of water. Bring to a boil, then cover and reduce heat to low. Cook for 30 to 40 minutes, or until the squash and apples are very soft.
Process the squash/apple mixture in batches, in a large food processor. Don't over-process. The mixture should be fairly thick. Return to the stockpot and add enough apple cider/juice to make the soup the consistency you like it. Serve piping hot with a small dollop of sour cream in the center.