Preheat oven to 400 degrees F. Line a baking sheet with parchment paper.
In a large mixing bowl, combine chopped cauliflower, turmeric, cinnamon, garlic powder, curry, and olive oil. Mix throughly. Place cauliflower on baking sheet and roast in the oven for 20-25 minutes or until golden brown.
In a large pot over medium-high heat, add onions, celery, and garlic. Cook until softened about 3-5 minutes.
Add sweet potatoes and vegetable stock to the pot. Bring to a boil. Add the roasted cauliflower and cook for another 25 minutes or until the vegetables are tender.
Add in whole can of coconut milk. Remove from heat and place in blender or use immersion blender.
Serve with toasted naan bread, crispy chickpeas, fresh oregano or parsley.