Pineapple Upside-Down Cake
["1/2 c. butter (oleo)", "1 c. brown sugar", "1 (20 oz.) can pineapple (slices)", "nuts (optional)", "1 c. flour", "1 tsp. baking powder", "1/8 tsp. salt", "3 eggs, separated", "1 c. sugar", "5 Tbsp. pineapple juice"]
["Melt butter in a 9 x 9-inch pan. Spread brown sugar evenly on top. Arrange pineapple slices on sugar. Fill spaces with nuts, if desired. Mix flour, baking powder and salt. Beat egg yolks until light and add sugar gradually. Add pineapple juice and flour mix. Fold in stiffly beaten egg whites. Pour batter over pineapple. Bake at 375\u00b0 for 30 to 35 minutes. Turn upside down on cake plate."]
["butter", "brown sugar", "pineapple", "nuts", "flour", "baking powder", "salt", "eggs", "sugar", "pineapple juice"]