Preheat the oven to 400.
Place the diced butternut squash on one sheet pan and the diced apple on a second sheet pan.
Season squash with 1 ½ tablespoons olive oil and a sprinkle of salt and pepper. Stir to get everything coated. Season apple with 1 tablespoon olive oil and stir to coat.
Roast squash and apple for 25-30 minutes, until tender and browned.
Meanwhile, heat remaining 1 ½ tablespoons olive oil in a large stock pot or dutch oven over medium heat.
Saute onion and celery for 6-8 minutes, until tender. Season with a pinch of salt and pepper.
Add chicken or vegetable stock and water and bring to a simmer.
Once the squash and apple are roasted, add them to the pot. Add ginger, nutmeg and cinnamon.
Use an immersion blender to blend the soup until smooth. (Alternatively, transfer the soup mixture to a regular blender. Just be sure to cover the blender well and be careful with the hot liquids.)
Season to taste with additional salt and pepper.
Serve with desired toppings (see notes) and enjoy!