Add the onion, carrots, butternut squash, and apple to the slow cooker. Pour the vegetable broth over all of the ingredients. Cook on low for 6 hours or on high for 3 to 4 hours or until the vegetables are soft.
Once vegetables are cooked and soft, puree the soup using an immersion blender. Add the cinnamon, nutmeg, and maple syrup. Season with salt and pepper, to taste. If you don't have an immersion blender, you can carefully transfer the soup to a blender (in batches) and puree until smooth. Pour the soup back into the slow cooker and season with spices and maple syrup.
While the soup is cooking in the slow cooker, make the maple roasted chickpeas. Preheat the oven to 375 degrees F. Rinse and drain the chickpeas and pat dry with a towel. Remove the skins by rolling them on the towel. In a small bowl, combine the canola oil, maple syrup, brown sugar, cinnamon, and salt. Place the chickpeas on a large baking sheet. Pour the maple syrup mixture over the chickpeas and toss until chickpeas are well coated. Place in the oven and bake for 40-45 minutes, stirring every 15 minutes or so. Remove from the oven when chickpeas are crunchy.
Pour soup into bowls and garnish with maple roasted chickpeas. Serve immediately.