In large pot, heat oil over medium heat. Add onion and cook, stirring often, until soft, about 5 minutes. Add garlic, curry powder, brown sugar and cumin and cook, stirring, 30 seconds. Add broth, squash and pears. Bring to a boil. Reduce heat and simmer, covered, until squash and pears are tender, 25 to 30 minutes. Purée mixture with immersion blender or transfer to food processor and process in batches. Garnish with cilantro. Serve warm.