Step 1

Toss the sweet potatoes with the cornstarch in a bowl to coat well. Add the mixture to a slow cooker and dot with the butter. Sprinkle over the brown sugar, pumpkin pie spice and cayenne. Pour in the vanilla, orange juice and 1/4 cup water. Season with salt. Place the lid on the slow cooker and cook on low, stirring once or twice, until the potatoes are tender, about 3 hours.

Step 2

Toss the potatoes once more and transfer to a serving dish. Sprinkle with the walnuts and parsley and serve.