Either roast squash in 400° oven for about 45-60 minutes, or peel and cut and boil 15-20 minutes until done.
Reserve water to use for vegetable broth.
Dice the onion.
Add coconut oil to the pan. When hot, add onion and leek.
Stir to coat, then cook, stirring occasionally, about 3 minutes until onion starts to look translucent.
Add apples, ginger and spices.
Stir and cook 1 minute.
Add vegetable stock (or water squash has cooked in) and bring to a boil.
Add lime juice, garlic and butternut squash.
Reduce heat and simmer, covered, about 10 minutes.
Add a bit more broth if needed.
Puree using an immersion blender or carefully in batches using a blender.
Thin with milk (dairy or non-dairy) if desired. (I didn't find this necessary as the soup had a great texture).
If you have a light-colored plastic immersion blender, wash it immediately to prevent the turmeric from staining.
Serve sprinkled with cinnamon and fresh lime juice, if desired.