Preheat oven to 400 degrees F. Line a baking pan with tinfoil (for easy clean up). Brush the flesh of the sweet potatoes with 2 teaspoons olive oil; roast flesh side down for 40-45 minutes, or until tender when pierced with a fork. Scoop out the flesh and discard the skins.
In a deep pot over medium heat, saute onions and remaining 2 teaspoons olive oil for 5 minutes, or until lightly browned. Add cooked potatoes, pineapple, and broth. Bring to a boil; reduce to low, and add brown sugar, peanut butter, and jalapeno; cook 7-8 minutes. Turn off heat; allow to cool 5-10 minutes before pureeing.
Working in batches, puree the soup in a blender until smooth; return to the pot over low heat. Add the coconut milk and salt, and stir occasionally until the soup is thoroughly combined and heated, about 10 minutes. Season to taste with salt. If you prefer a thinner soup, simply add a bit more water or broth until desired consistency is reached. Makes 4-6 servings
Garnish individual bowls with thinly sliced fresh cilantro and chopped peanuts.
