Remove and random pots and pans from your oven.
Preheat oven to 375F.
Wash and dry the red peppers.
Line a cookie sheet with aluminum foil and use some of the oil to fully coat each of the peppers and lay them on the cookie sheet.
In a bowl put the onion and sweet potato and add half the remaining oil, salt and pepper and mix.
Add sweet potato and onion mixture to the cookie sheet and roast for 25-30 minutes, then set aside.
When the red peppers have cooled, you can remove the skins, stem and seeds.
Heat the rest of the oil in a large heavy bottom pot (preferably cast iron), add celery, carrots and cook for about 5-6 minutes.
Then add the garlic, red peppers, sweet potatos, onions and cook for another 5 minutes.
Add in the vegetable broth and bring it up to a boil, once it boils then reduce the heat and simmer for 20 minutes uncovered.
Remove from the heat and using an immersion blender, puree until it is very smooth.
Optional step - Carefully transfer the hot mixture to the food mill and run all the mixture through (this helps make it velvety smooth).
Return the mixture to the pot and add the coconut milk, taste and add salt and pepper as necessary and serve hot.