Rich Silver Cake
["3 1/2 c. flour", "2 c. sugar", "1 tsp. salt", "5 tsp. baking powder", "1 c. soft shortening", "1 1/3 c. thin milk (half water)", "2 tsp. flavoring (lemon or vanilla)", "6 egg whites (unbeaten)"]
["Sift together flour, sugar, salt and baking powder.", "Add shortening, milk and flavoring.", "Beat for 2 minutes.", "Add egg whites.", "Beat 2 minutes.", "Pour into 3 greased and floured pans. (Batter may appear curdled.)", "Bake at 350\u00b0 until done in 9-inch pans for 30 to 35 minutes, in 8-inch pans bake 25 to 30 minutes, or 13 x 9 x 2 1/2-inch pan bake for 1 hour."]
["flour", "sugar", "salt", "baking powder", "shortening", "thin milk", "vanilla", "egg whites"]