Preheat an oven to 350 degrees F (175 degrees C). Sift the flour 4 times with the baking powder and salt.
Cream the butter with 1 1/2 cups sugar in a large mixing bowl. Add the sifted ingredients alternately with the milk to the creamed mixture. Beat the egg whites until they are stiff, but not dry. Fold them into the batter.
Pour the batter into three 9-inch round cake pans. Bake in the preheated oven approximately 30 minutes. Place on wire racks until cool.
While the layers are cooling make the filling. Combine the egg yolks, 1/4 cup sugar, cornstarch, and pineapple juice in the top of a double boiler. Cook until thick; stir often. Cool, and spread filling on top of two of the layers. Sprinkle nuts and crushed pineapple on top of filling. Place these two layers one on top of the other, and place third layer on the top. Frost with any white frosting.
