I had some butternut squash to use as I had cut one for another recipe. I found this recipe in the 'delicious' magazine in the November 2004 edition. I realised that I also had lots of fresh coriander (cilantro) and sour cream sitting in the fridge, so this recipe was just made for the situation I was in! In this recipe, the squash is roasted first to enhance its flavour. I love the combination of the smooth butternut squash purée and the freshness of the coriander. But what really rounds the soup off is the cold and creamy sour cream and the roasted, crunchy pumpkin seeds. This soup makes a great starter, but also a nice meal when served with bread and or salad. The original recipe calls for kabocha squash or pumpkin.