Reduce the heat to low and simmer for 15-20 minutes, or until sweet potatoes are tender. While cooking, add turmeric, garlic powder, and salt. Taste and adjust seasonings as needed. After 10 minutes add 1 can of coconut milk and stir well.
When tho soup is done you can use the immersion blender to puree the soup completely or you can transfer this mixture into a blender and blend until smooth.
If the soup is too thick you can add 1 more cup of water, transfer the blended soup back to your pot and reheat for a couple of minutes before serving.