Heat the oil in a Dutch oven or large saucepan over medium heat. Add the onion and cook, stirring frequently, until tender, 5 minutes. Stir in the garlic and cook until fragrant, 1 more minute.
Add the squash, apple, pear, curry powder, cinnamon, and ginger and stir to combine.
Stir in the broth, increase the heat to high, cover, and bring to a boil. Once boiling, reduce the heat and maintain at a low boil, covered, until the squash is tender, about 30 minutes.
Use an immersion blender to puree the soup. If you don't have an immersion blender, let cool for about 15 minutes, transfer to a blender, and puree in batches until very smooth. Transfer back to the pot, reheat, and season with salt and pepper to taste. Serve.
Topping ideas: toasted, chopped walnuts, roasted pumpkin seeds, chopped chives, plain Greek yogurt