This recipe is from Emeril Lagasse: http://emerils.com/126662/african-peanut-soup
Heat the oil in a soup pot over medium-high heat. Add the curry powder and stir for about a minute to "wake up" the flavors in the curry powder. Add the onions and stir occasionally until they begin to soften. Next add the garlic and cook for another minute, stirring.
Add the cubed sweet potatoes, broth and tomatoes to the pot. Bring all of this to a boil, then reduce the heat and simmer for about 20 minutes.
Add the salt, pepper, cayenne pepper, peanut butter, and coconut milk. Simmer for another 20 minutes.
Turn off heat and puree with a hand immersion blender if you have one, (I highly recommend. They are inexpensive and so helpful!) Or in several batches, blend in food processor or blender.
Top with chopped cilantro and peanuts, if desired.