In a food processor, blend the coconut milk, turmeric, cumin, and coriander until smooth.
In a soup pan on medium heat, melt the coconut oil. Add the onion and sauté until translucent and starting to brown, 6-8 minutes. Add the garlic and sauté about 1 minute.
Deglaze the pan with a few tablespoons of the spiced turmeric-coconut milk, scraping up the browned bits from the bottom of the pan.
Add the remainder of the turmeric-coconut milk to the dutch oven, along with the carrots, celery, chicken bone broth, roasted chicken, sea salt, and pepper. Bring to a boil, then reduce to low and simmer until the vegetables are tender and the soup is slightly thick, 20-25 minutes.