Preheat oven to 450 degrees. Slice squash lengthwise and scoop out seeds. Drizzle with olive oil, salt, and pepper. Roast squash flesh side down for 40 minutes or until tender. Let cool slightly and scoop out flesh and discard tough peel. Set squash aside.
In a heavy bottom pot, on medium high heat, sauté shallots until translucent. Add garlic and stir; allow to get fragrant but not brown. Add squash, all spice, salt, pepper, maple syrup, and chicken stock. Stir to combine and simmer, letting the flavors meld.
Using an immersion or standard blender, blend all ingredients until smooth consistency. If soup is too thick, add chicken stock or water to desired consistency. Finally, blend in 2-3 tablespoons of whole butter for richness.
Garnish with a dollop of whipped cream, a few pumpkin seeds, and a drizzle of chili oil.