Heat 2 tablespoons of peanut oil in a large Dutch oven or stockpot over medium-high heat.
Add curry powder and cook, stirring constantly for 1 minute.
Add onions and cook, stirring occasionally, for 2 minutes.
Add garlic and cook for 1 more minute.
Stir in sweet potatoes, chicken broth and tomatoes, and bring soup to a boil.
Simmer, covered, 20 to 30 minutes.
In a large skillet, heat the remaining teaspoon of peanut oil.
Add the turkey and cook, stirring with a wooden spoon to break up any clumps until cooked through.
Season with ½ teaspoon salt and ¼ teaspoon black pepper.
Drain on paper towels.
Add cooked ground turkey, the remaining ½ teaspoon salt, cayenne, peanut butter, and coconut milk to the soup, stirring to combine.
Bring mixture to a simmer and cook for 20 minutes.
