Heat the coconut oil in a large skillet or pot over medium heat. Add the finely chopped onion and sauté until translucent and softened, about 5-7 minutes.
Add the minced garlic and grated ginger to the skillet, cooking for an additional 1-2 minutes until fragrant.
Add the chicken pieces to the skillet and cook until browned on all sides.
Stir in the diced sweet potatoes, coconut milk, chicken broth, curry powder, ground turmeric, ground cumin, ground coriander, ground cinnamon, and ground cardamom. Mix well to combine.
Bring the mixture to a simmer. Reduce heat to low and cover. Cook for 20-25 minutes, or until the sweet potatoes are tender and the chicken is cooked through.
Adjust seasoning with additional sea salt to taste if needed.
Serve the curry garnished with chopped fresh cilantro and lime wedges on the side.