Prepare cake according to directions on package, pouring batter into 3 prepared round pans. Bake as directed on package, but adjust time for three layers.
Filling: 1 (20 ounce) can crushed pineapple in heavy syrup 1/4 cup granulated sugar 2 egg yolks 3 level tablespoons flour
Mix pineapple, egg yolks, flour and sugar. Place over medium heat and cook until thick, stirring constantly. Use filling between layers.
Icing: 2 egg whites 1 1/2 cups granulated sugar 2 tablespoons white corn syrup 5 tablespoons water 1/8 teaspoon cream of tartar 1 teaspoon vanilla extract
Cook all ingredients in top of double boiler over boiling water. Mix with hand mixer until icing will stand in a peak. Ice top and sides of cake.
