Heat oil in a large stock pot over medium heat. Add garlic, onions, celery and carrots. Saute 5 minutes. Add sweet potato, tomato, broth and coconut milk. Bring to a boil and simmer, covered, until vegetables are cooked through, and sweet potato and carrots are soft.Add the fish and simmer until the fish is opaque and cooked through, about 8 minutes. Add salt, pepper, hot sauce or coconut aminos to taste.Freeze in portions.