Warm sugar, butter, bourbon, cinnamon and nutmeg in a saucepan. Slice potatoes 1-inch thick and place in a large mixing bowl. Pour half of the butter bourbon mixture over potatoes, stir until well coated.
Place potatoes in a sprayed 13 x 9-inch baking dish. Bake for 30 minutes; remove pan from the oven and pour remaining sauce over top. Return to oven and bake an additional 10 to 15 minutes until potatoes are cooked through (fork tender).
Recipe Note: Grand Marnier can be substituted for bourbon