Preheat oven to 350º
Line a large baking sheet with unbleached parchment paper.
Using a peeler, remove the outer skin of the squash, then slice it in half, longways. Scoop out the seeds and guts with a spoon. Chop Squash into large 1-inch cubes.
Peel and core the apple, chop into quarters.
Place the squash cubes and apple on the baking sheet. Drizzle with 1 tbsp of avocado or olive oil, mix well making sure all the squash cubes are evenly coated.
Place in the oven and bake for 35-40 minutes or until juices begin to release and the squash is soft.
Once the squash is roasted, remove from the oven and set aside.
Coat the bottom of a large pot with the remaining 1-2 tbsp of avocado or olive oil. Turn the heat to medium-low, add onion and garlic, sauté for a few minutes or until onion is transparent and fragrant.
Stir in the squash and apple cubes, then pour in the vegetable broth and milk.
Cover and bring to a boil and then turn down the heat to low. Stir in the spices and salt. Cover and let simmer for about 15 minutes.
Remove from heat and remove the lid to allow the steam to release. Let cool for a few minutes before transferring to a blender.
Once the soup is cool enough to handle, pour into a blender and blend on high until smooth (or alternatively blend everything right in the pot with an immersion blender).
If using a regular blender, pour back into pot and heat over low, if necessary.