FoodNetwork.com has an easy recipe for squash soup. It has four main ingredients: butternut squash, onion, butter and chicken stock, plus seasonings. Preparation time, including cutting and puréeing the squash, is 20 minutes.
Once Upon a Chef's website has a simple squash soup recipe. It provides instructions for using packages of precut butternut squash or fresh whole squash. The recipe also calls for chopped red pepper, garlic and heavy cream. Preparation time is 15 minutes.
RealSimple also has an uncomplicated squash and parsnip soup recipe on its website. In addition to the title ingredients, the recipe requires four more items, plus seasonings and garnish. Cooks can prepare the soup within 25 minutes.