To prepare a sweet potato souffle 0 recipe, you will need: Sweet potato: Peel and cut the sweet potatoes in half lengthwise. Cut each half into 1/4-inch cubes. Melt the butter over medium-low heat. Add the sugar and stir. Cook, stirring constantly, until the mixture is completely melted, about 5 minutes. Remove from the heat and add the vanilla. Beat the egg whites with an electric mixer until stiff peaks form. Fold the whipped cream into the batter. Pour into an oiled souffle dish. Bake in the oven at 325?F for 20 to 25 minutes, or until golden brown. Serve warm or at room temperature.