Chop leeks, mince garlic, slice ginger, and cut sweet potato and carrots into chunks. Set aside.
Add butter to a Dutch oven or stock pot over medium heat. Gently stir the butter as it melts. It will sizzle, foam, and turn a deeper color. You should see small bits (the milk solids) at the bottom of the pan that are golden brown. (About three minutes).
Add leeks, garlic, and ginger to pot with browned butter and allow to cook down until fragrant and tender (about 5 minutes).
Increase heat to medium high and add prepared sweet potato, carrots, bone broth, cayenne pepper, chili powder, cinnamon, sea salt, black pepper to pot. Bring to a low boil.
Reduce heat to medium low, cover, and simmer for about 25 minutes or until sweet potato and carrot are tender.
Transfer solid ingredients and about two cups of liquid to a blender or food processor and pulse until smooth and uniform. You can, alternatively, use an immersion blender for this step.
Return soup to pot and stir well to incorporate remaining liquid. Serve with sprinkles of chili powder and cayenne pepper and a drizzle of olive oil.