Preheat oven to 400 degrees F.
Combine pears, squash, tomatoes, leek, garlic, oil, salt and pepper in a large bowl; toss to coat. Spread evenly on two large rimmed baking sheets. Roast, stirring occasionally, until the vegetables are tender, about 45 minutes. (Don’t be afraid of the charred bits from roasting, that’s added flavor.)
*Place half the vegetables and 2 cups broth in a blender; puree until smooth. Transfer to a large stock pot. Puree the remaining vegetables and 2 cups broth. Add to the pan.
*Alternatively, add the roasted vegetables to hot chicken stock in a dutch oven and use an immersion blender. The soup is done in minutes, with no worries of exploding hot soup from your blender and to minimize clean up.
Cook the soup over medium-low heat, stirring, until hot, about 10 minutes.
Serve with a garnish of crumbled blue cheese, chopped walnuts, crumbled bacon or crispy prosciutto.