Preheat oven to 350 degrees. Arrange sweet potatoes in a 9-by-13-inch baking dish. Add sugar and bourbon and toss to combine; season with salt and pepper. Bake until sweet potatoes are tender and glazed, 1 to 1 1/2 hours, tossing every 30 minutes. Stir in butter before serving.
Place the sweet potatoes in the oven after the turkey has roasted for an hour.
This recipe is so easy and everyone loves it. I did not have bourbon so used Bushmills and it was fine. So I have renamed it Bushmills Sweet Potatoes, which of course is popular with the Irish crowd!!